2012-11-29 12:28:09 +08:00
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/*
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f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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* fs/f2fs/gc.c
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*
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* Copyright (c) 2012 Samsung Electronics Co., Ltd.
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* http://www.samsung.com/
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/fs.h>
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#include <linux/module.h>
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#include <linux/backing-dev.h>
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#include <linux/init.h>
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#include <linux/f2fs_fs.h>
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#include <linux/kthread.h>
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#include <linux/delay.h>
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#include <linux/freezer.h>
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#include <linux/blkdev.h>
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#include "f2fs.h"
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#include "node.h"
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#include "segment.h"
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#include "gc.h"
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2013-04-23 15:42:53 +08:00
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#include <trace/events/f2fs.h>
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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static struct kmem_cache *winode_slab;
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static int gc_thread_func(void *data)
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{
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struct f2fs_sb_info *sbi = data;
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2013-08-04 22:09:40 +08:00
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struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
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long wait_ms;
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2013-08-04 22:09:40 +08:00
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wait_ms = gc_th->min_sleep_time;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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do {
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if (try_to_freeze())
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continue;
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else
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wait_event_interruptible_timeout(*wq,
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kthread_should_stop(),
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msecs_to_jiffies(wait_ms));
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if (kthread_should_stop())
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break;
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2013-01-29 17:30:07 +08:00
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if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
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2013-08-04 22:09:40 +08:00
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wait_ms = increase_sleep_time(gc_th, wait_ms);
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2013-01-29 17:30:07 +08:00
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continue;
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}
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|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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/*
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* [GC triggering condition]
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* 0. GC is not conducted currently.
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* 1. There are enough dirty segments.
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* 2. IO subsystem is idle by checking the # of writeback pages.
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* 3. IO subsystem is idle by checking the # of requests in
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* bdev's request list.
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*
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* Note) We have to avoid triggering GCs too much frequently.
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* Because it is possible that some segments can be
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* invalidated soon after by user update or deletion.
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* So, I'd like to wait some time to collect dirty segments.
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*/
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if (!mutex_trylock(&sbi->gc_mutex))
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continue;
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if (!is_idle(sbi)) {
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2013-08-04 22:09:40 +08:00
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wait_ms = increase_sleep_time(gc_th, wait_ms);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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mutex_unlock(&sbi->gc_mutex);
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continue;
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}
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if (has_enough_invalid_blocks(sbi))
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2013-08-04 22:09:40 +08:00
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wait_ms = decrease_sleep_time(gc_th, wait_ms);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
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else
|
2013-08-04 22:09:40 +08:00
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wait_ms = increase_sleep_time(gc_th, wait_ms);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
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|
2013-10-22 19:56:10 +08:00
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stat_inc_bggc_count(sbi);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
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|
2013-02-04 14:11:17 +08:00
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/* if return value is not zero, no victim was selected */
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if (f2fs_gc(sbi))
|
2013-08-04 22:09:40 +08:00
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wait_ms = gc_th->no_gc_sleep_time;
|
2013-10-24 12:31:34 +08:00
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2013-10-24 13:19:18 +08:00
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/* balancing f2fs's metadata periodically */
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f2fs_balance_fs_bg(sbi);
|
2013-10-24 12:31:34 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
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} while (!kthread_should_stop());
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return 0;
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}
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int start_gc_thread(struct f2fs_sb_info *sbi)
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{
|
2012-12-01 09:56:13 +08:00
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struct f2fs_gc_kthread *gc_th;
|
2013-02-02 22:52:28 +08:00
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dev_t dev = sbi->sb->s_bdev->bd_dev;
|
2013-05-26 10:05:32 +08:00
|
|
|
int err = 0;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-02-04 09:05:09 +08:00
|
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|
if (!test_opt(sbi, BG_GC))
|
2013-05-26 10:05:32 +08:00
|
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|
goto out;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
gc_th = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
|
2013-05-26 10:05:32 +08:00
|
|
|
if (!gc_th) {
|
|
|
|
|
err = -ENOMEM;
|
|
|
|
|
goto out;
|
|
|
|
|
}
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-08-04 22:09:40 +08:00
|
|
|
gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME;
|
|
|
|
|
gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME;
|
|
|
|
|
gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME;
|
|
|
|
|
|
2013-08-04 22:10:15 +08:00
|
|
|
gc_th->gc_idle = 0;
|
|
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
sbi->gc_thread = gc_th;
|
|
|
|
|
init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head);
|
|
|
|
|
sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi,
|
2013-02-02 22:52:28 +08:00
|
|
|
"f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev));
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (IS_ERR(gc_th->f2fs_gc_task)) {
|
2013-05-26 10:05:32 +08:00
|
|
|
err = PTR_ERR(gc_th->f2fs_gc_task);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
kfree(gc_th);
|
2013-02-02 22:52:42 +08:00
|
|
|
sbi->gc_thread = NULL;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
2013-05-26 10:05:32 +08:00
|
|
|
out:
|
|
|
|
|
return err;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void stop_gc_thread(struct f2fs_sb_info *sbi)
|
|
|
|
|
{
|
|
|
|
|
struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
|
|
|
|
|
if (!gc_th)
|
|
|
|
|
return;
|
|
|
|
|
kthread_stop(gc_th->f2fs_gc_task);
|
|
|
|
|
kfree(gc_th);
|
|
|
|
|
sbi->gc_thread = NULL;
|
|
|
|
|
}
|
|
|
|
|
|
2013-08-04 22:10:15 +08:00
|
|
|
static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
{
|
2013-08-04 22:10:15 +08:00
|
|
|
int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY;
|
|
|
|
|
|
|
|
|
|
if (gc_th && gc_th->gc_idle) {
|
|
|
|
|
if (gc_th->gc_idle == 1)
|
|
|
|
|
gc_mode = GC_CB;
|
|
|
|
|
else if (gc_th->gc_idle == 2)
|
|
|
|
|
gc_mode = GC_GREEDY;
|
|
|
|
|
}
|
|
|
|
|
return gc_mode;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
|
|
|
|
|
int type, struct victim_sel_policy *p)
|
|
|
|
|
{
|
|
|
|
|
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
|
|
|
|
|
|
2013-03-31 12:49:18 +08:00
|
|
|
if (p->alloc_mode == SSR) {
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
p->gc_mode = GC_GREEDY;
|
|
|
|
|
p->dirty_segmap = dirty_i->dirty_segmap[type];
|
f2fs: optimize gc for better performance
This patch improves the gc efficiency by optimizing the victim
selection policy. With this optimization, the random re-write
performance could increase up to 20%.
For f2fs, when disk is in shortage of free spaces, gc will selects
dirty segments and moves valid blocks around for making more space
available. The gc cost of a segment is determined by the valid blocks
in the segment. The less the valid blocks, the higher the efficiency.
The ideal victim segment is the one that has the most garbage blocks.
Currently, it searches up to 20 dirty segments for a victim segment.
The selected victim is not likely the best victim for gc when there
are much more dirty segments. Why not searching more dirty segments
for a better victim? The cost of searching dirty segments is
negligible in comparison to moving blocks.
In this patch, it enlarges the MAX_VICTIM_SEARCH to 4096 to make
the search more aggressively for a possible better victim. Since
it also applies to victim selection for SSR, it will likely improve
the SSR efficiency as well.
The test case is simple. It creates as many files until the disk full.
The size for each file is 32KB. Then it writes as many as 100000
records of 4KB size to random offsets of random files in sync mode.
The testing was done on a 2GB partition of a SDHC card. Let's see the
test result of f2fs without and with the patch.
---------------------------------------
2GB partition, SDHC
create 52023 files of size 32768 bytes
random re-write 100000 records of 4KB
---------------------------------------
| file creation (s) | rewrite time (s) | gc count | gc garbage blocks |
[no patch] 341 4227 1174 174840
[patched] 324 2958 645 106682
It's obvious that, with the patch, f2fs finishes the test in 20+% less
time than without the patch. And internally it does much less gc with
higher efficiency than before.
Since the performance improvement is related to gc, it might not be so
obvious for other tests that do not trigger gc as often as this one (
This is because f2fs selects dirty segments for SSR use most of the
time when free space is in shortage). The well-known iozone test tool
was not used for benchmarking the patch becuase it seems do not have
a test case that performs random re-write on a full disk.
This patch is the revised version based on the suggestion from
Jaegeuk Kim.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: suggested simpler solution]
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 12:45:26 +08:00
|
|
|
p->max_search = dirty_i->nr_dirty[type];
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
p->ofs_unit = 1;
|
|
|
|
|
} else {
|
2013-08-04 22:10:15 +08:00
|
|
|
p->gc_mode = select_gc_type(sbi->gc_thread, gc_type);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
p->dirty_segmap = dirty_i->dirty_segmap[DIRTY];
|
f2fs: optimize gc for better performance
This patch improves the gc efficiency by optimizing the victim
selection policy. With this optimization, the random re-write
performance could increase up to 20%.
For f2fs, when disk is in shortage of free spaces, gc will selects
dirty segments and moves valid blocks around for making more space
available. The gc cost of a segment is determined by the valid blocks
in the segment. The less the valid blocks, the higher the efficiency.
The ideal victim segment is the one that has the most garbage blocks.
Currently, it searches up to 20 dirty segments for a victim segment.
The selected victim is not likely the best victim for gc when there
are much more dirty segments. Why not searching more dirty segments
for a better victim? The cost of searching dirty segments is
negligible in comparison to moving blocks.
In this patch, it enlarges the MAX_VICTIM_SEARCH to 4096 to make
the search more aggressively for a possible better victim. Since
it also applies to victim selection for SSR, it will likely improve
the SSR efficiency as well.
The test case is simple. It creates as many files until the disk full.
The size for each file is 32KB. Then it writes as many as 100000
records of 4KB size to random offsets of random files in sync mode.
The testing was done on a 2GB partition of a SDHC card. Let's see the
test result of f2fs without and with the patch.
---------------------------------------
2GB partition, SDHC
create 52023 files of size 32768 bytes
random re-write 100000 records of 4KB
---------------------------------------
| file creation (s) | rewrite time (s) | gc count | gc garbage blocks |
[no patch] 341 4227 1174 174840
[patched] 324 2958 645 106682
It's obvious that, with the patch, f2fs finishes the test in 20+% less
time than without the patch. And internally it does much less gc with
higher efficiency than before.
Since the performance improvement is related to gc, it might not be so
obvious for other tests that do not trigger gc as often as this one (
This is because f2fs selects dirty segments for SSR use most of the
time when free space is in shortage). The well-known iozone test tool
was not used for benchmarking the patch becuase it seems do not have
a test case that performs random re-write on a full disk.
This patch is the revised version based on the suggestion from
Jaegeuk Kim.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: suggested simpler solution]
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 12:45:26 +08:00
|
|
|
p->max_search = dirty_i->nr_dirty[DIRTY];
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
p->ofs_unit = sbi->segs_per_sec;
|
|
|
|
|
}
|
f2fs: optimize gc for better performance
This patch improves the gc efficiency by optimizing the victim
selection policy. With this optimization, the random re-write
performance could increase up to 20%.
For f2fs, when disk is in shortage of free spaces, gc will selects
dirty segments and moves valid blocks around for making more space
available. The gc cost of a segment is determined by the valid blocks
in the segment. The less the valid blocks, the higher the efficiency.
The ideal victim segment is the one that has the most garbage blocks.
Currently, it searches up to 20 dirty segments for a victim segment.
The selected victim is not likely the best victim for gc when there
are much more dirty segments. Why not searching more dirty segments
for a better victim? The cost of searching dirty segments is
negligible in comparison to moving blocks.
In this patch, it enlarges the MAX_VICTIM_SEARCH to 4096 to make
the search more aggressively for a possible better victim. Since
it also applies to victim selection for SSR, it will likely improve
the SSR efficiency as well.
The test case is simple. It creates as many files until the disk full.
The size for each file is 32KB. Then it writes as many as 100000
records of 4KB size to random offsets of random files in sync mode.
The testing was done on a 2GB partition of a SDHC card. Let's see the
test result of f2fs without and with the patch.
---------------------------------------
2GB partition, SDHC
create 52023 files of size 32768 bytes
random re-write 100000 records of 4KB
---------------------------------------
| file creation (s) | rewrite time (s) | gc count | gc garbage blocks |
[no patch] 341 4227 1174 174840
[patched] 324 2958 645 106682
It's obvious that, with the patch, f2fs finishes the test in 20+% less
time than without the patch. And internally it does much less gc with
higher efficiency than before.
Since the performance improvement is related to gc, it might not be so
obvious for other tests that do not trigger gc as often as this one (
This is because f2fs selects dirty segments for SSR use most of the
time when free space is in shortage). The well-known iozone test tool
was not used for benchmarking the patch becuase it seems do not have
a test case that performs random re-write on a full disk.
This patch is the revised version based on the suggestion from
Jaegeuk Kim.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: suggested simpler solution]
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 12:45:26 +08:00
|
|
|
|
2014-01-08 12:45:08 +08:00
|
|
|
if (p->max_search > sbi->max_victim_search)
|
|
|
|
|
p->max_search = sbi->max_victim_search;
|
f2fs: optimize gc for better performance
This patch improves the gc efficiency by optimizing the victim
selection policy. With this optimization, the random re-write
performance could increase up to 20%.
For f2fs, when disk is in shortage of free spaces, gc will selects
dirty segments and moves valid blocks around for making more space
available. The gc cost of a segment is determined by the valid blocks
in the segment. The less the valid blocks, the higher the efficiency.
The ideal victim segment is the one that has the most garbage blocks.
Currently, it searches up to 20 dirty segments for a victim segment.
The selected victim is not likely the best victim for gc when there
are much more dirty segments. Why not searching more dirty segments
for a better victim? The cost of searching dirty segments is
negligible in comparison to moving blocks.
In this patch, it enlarges the MAX_VICTIM_SEARCH to 4096 to make
the search more aggressively for a possible better victim. Since
it also applies to victim selection for SSR, it will likely improve
the SSR efficiency as well.
The test case is simple. It creates as many files until the disk full.
The size for each file is 32KB. Then it writes as many as 100000
records of 4KB size to random offsets of random files in sync mode.
The testing was done on a 2GB partition of a SDHC card. Let's see the
test result of f2fs without and with the patch.
---------------------------------------
2GB partition, SDHC
create 52023 files of size 32768 bytes
random re-write 100000 records of 4KB
---------------------------------------
| file creation (s) | rewrite time (s) | gc count | gc garbage blocks |
[no patch] 341 4227 1174 174840
[patched] 324 2958 645 106682
It's obvious that, with the patch, f2fs finishes the test in 20+% less
time than without the patch. And internally it does much less gc with
higher efficiency than before.
Since the performance improvement is related to gc, it might not be so
obvious for other tests that do not trigger gc as often as this one (
This is because f2fs selects dirty segments for SSR use most of the
time when free space is in shortage). The well-known iozone test tool
was not used for benchmarking the patch becuase it seems do not have
a test case that performs random re-write on a full disk.
This patch is the revised version based on the suggestion from
Jaegeuk Kim.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: suggested simpler solution]
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 12:45:26 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
p->offset = sbi->last_victim[p->gc_mode];
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
|
|
|
|
|
struct victim_sel_policy *p)
|
|
|
|
|
{
|
2013-02-05 12:19:28 +08:00
|
|
|
/* SSR allocates in a segment unit */
|
|
|
|
|
if (p->alloc_mode == SSR)
|
|
|
|
|
return 1 << sbi->log_blocks_per_seg;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (p->gc_mode == GC_GREEDY)
|
|
|
|
|
return (1 << sbi->log_blocks_per_seg) * p->ofs_unit;
|
|
|
|
|
else if (p->gc_mode == GC_CB)
|
|
|
|
|
return UINT_MAX;
|
|
|
|
|
else /* No other gc_mode */
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
|
|
|
|
|
{
|
|
|
|
|
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
|
2013-03-31 12:26:03 +08:00
|
|
|
unsigned int hint = 0;
|
|
|
|
|
unsigned int secno;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* If the gc_type is FG_GC, we can select victim segments
|
|
|
|
|
* selected by background GC before.
|
|
|
|
|
* Those segments guarantee they have small valid blocks.
|
|
|
|
|
*/
|
2013-03-31 12:26:03 +08:00
|
|
|
next:
|
|
|
|
|
secno = find_next_bit(dirty_i->victim_secmap, TOTAL_SECS(sbi), hint++);
|
|
|
|
|
if (secno < TOTAL_SECS(sbi)) {
|
|
|
|
|
if (sec_usage_check(sbi, secno))
|
|
|
|
|
goto next;
|
|
|
|
|
clear_bit(secno, dirty_i->victim_secmap);
|
|
|
|
|
return secno * sbi->segs_per_sec;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
return NULL_SEGNO;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno)
|
|
|
|
|
{
|
|
|
|
|
struct sit_info *sit_i = SIT_I(sbi);
|
|
|
|
|
unsigned int secno = GET_SECNO(sbi, segno);
|
|
|
|
|
unsigned int start = secno * sbi->segs_per_sec;
|
|
|
|
|
unsigned long long mtime = 0;
|
|
|
|
|
unsigned int vblocks;
|
|
|
|
|
unsigned char age = 0;
|
|
|
|
|
unsigned char u;
|
|
|
|
|
unsigned int i;
|
|
|
|
|
|
|
|
|
|
for (i = 0; i < sbi->segs_per_sec; i++)
|
|
|
|
|
mtime += get_seg_entry(sbi, start + i)->mtime;
|
|
|
|
|
vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
|
|
|
|
|
|
|
|
|
|
mtime = div_u64(mtime, sbi->segs_per_sec);
|
|
|
|
|
vblocks = div_u64(vblocks, sbi->segs_per_sec);
|
|
|
|
|
|
|
|
|
|
u = (vblocks * 100) >> sbi->log_blocks_per_seg;
|
|
|
|
|
|
|
|
|
|
/* Handle if the system time is changed by user */
|
|
|
|
|
if (mtime < sit_i->min_mtime)
|
|
|
|
|
sit_i->min_mtime = mtime;
|
|
|
|
|
if (mtime > sit_i->max_mtime)
|
|
|
|
|
sit_i->max_mtime = mtime;
|
|
|
|
|
if (sit_i->max_mtime != sit_i->min_mtime)
|
|
|
|
|
age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime),
|
|
|
|
|
sit_i->max_mtime - sit_i->min_mtime);
|
|
|
|
|
|
|
|
|
|
return UINT_MAX - ((100 * (100 - u) * age) / (100 + u));
|
|
|
|
|
}
|
|
|
|
|
|
2013-09-13 08:38:54 +08:00
|
|
|
static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi,
|
|
|
|
|
unsigned int segno, struct victim_sel_policy *p)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
{
|
|
|
|
|
if (p->alloc_mode == SSR)
|
|
|
|
|
return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
|
|
|
|
|
|
|
|
|
|
/* alloc_mode == LFS */
|
|
|
|
|
if (p->gc_mode == GC_GREEDY)
|
|
|
|
|
return get_valid_blocks(sbi, segno, sbi->segs_per_sec);
|
|
|
|
|
else
|
|
|
|
|
return get_cb_cost(sbi, segno);
|
|
|
|
|
}
|
|
|
|
|
|
2012-11-29 12:28:09 +08:00
|
|
|
/*
|
2013-03-19 07:03:35 +08:00
|
|
|
* This function is called from two paths.
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
* One is garbage collection and the other is SSR segment selection.
|
|
|
|
|
* When it is called during GC, it just gets a victim segment
|
|
|
|
|
* and it does not remove it from dirty seglist.
|
|
|
|
|
* When it is called from SSR segment selection, it finds a segment
|
|
|
|
|
* which has minimum valid blocks and removes it from dirty seglist.
|
|
|
|
|
*/
|
|
|
|
|
static int get_victim_by_default(struct f2fs_sb_info *sbi,
|
|
|
|
|
unsigned int *result, int gc_type, int type, char alloc_mode)
|
|
|
|
|
{
|
|
|
|
|
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
|
|
|
|
|
struct victim_sel_policy p;
|
2013-06-01 15:20:26 +08:00
|
|
|
unsigned int secno, max_cost;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
int nsearched = 0;
|
|
|
|
|
|
|
|
|
|
p.alloc_mode = alloc_mode;
|
|
|
|
|
select_policy(sbi, gc_type, type, &p);
|
|
|
|
|
|
|
|
|
|
p.min_segno = NULL_SEGNO;
|
2013-06-01 15:20:26 +08:00
|
|
|
p.min_cost = max_cost = get_max_cost(sbi, &p);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
mutex_lock(&dirty_i->seglist_lock);
|
|
|
|
|
|
|
|
|
|
if (p.alloc_mode == LFS && gc_type == FG_GC) {
|
|
|
|
|
p.min_segno = check_bg_victims(sbi);
|
|
|
|
|
if (p.min_segno != NULL_SEGNO)
|
|
|
|
|
goto got_it;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
while (1) {
|
|
|
|
|
unsigned long cost;
|
2013-03-31 12:26:03 +08:00
|
|
|
unsigned int segno;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
segno = find_next_bit(p.dirty_segmap,
|
|
|
|
|
TOTAL_SEGS(sbi), p.offset);
|
|
|
|
|
if (segno >= TOTAL_SEGS(sbi)) {
|
|
|
|
|
if (sbi->last_victim[p.gc_mode]) {
|
|
|
|
|
sbi->last_victim[p.gc_mode] = 0;
|
|
|
|
|
p.offset = 0;
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
}
|
2013-09-13 08:38:54 +08:00
|
|
|
|
|
|
|
|
p.offset = segno + p.ofs_unit;
|
|
|
|
|
if (p.ofs_unit > 1)
|
|
|
|
|
p.offset -= segno % p.ofs_unit;
|
|
|
|
|
|
2013-03-31 12:26:03 +08:00
|
|
|
secno = GET_SECNO(sbi, segno);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-03-31 12:26:03 +08:00
|
|
|
if (sec_usage_check(sbi, secno))
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
2013-03-31 12:26:03 +08:00
|
|
|
if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
cost = get_gc_cost(sbi, segno, &p);
|
|
|
|
|
|
|
|
|
|
if (p.min_cost > cost) {
|
|
|
|
|
p.min_segno = segno;
|
|
|
|
|
p.min_cost = cost;
|
2013-09-13 08:38:54 +08:00
|
|
|
} else if (unlikely(cost == max_cost)) {
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
2013-09-13 08:38:54 +08:00
|
|
|
}
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
f2fs: optimize gc for better performance
This patch improves the gc efficiency by optimizing the victim
selection policy. With this optimization, the random re-write
performance could increase up to 20%.
For f2fs, when disk is in shortage of free spaces, gc will selects
dirty segments and moves valid blocks around for making more space
available. The gc cost of a segment is determined by the valid blocks
in the segment. The less the valid blocks, the higher the efficiency.
The ideal victim segment is the one that has the most garbage blocks.
Currently, it searches up to 20 dirty segments for a victim segment.
The selected victim is not likely the best victim for gc when there
are much more dirty segments. Why not searching more dirty segments
for a better victim? The cost of searching dirty segments is
negligible in comparison to moving blocks.
In this patch, it enlarges the MAX_VICTIM_SEARCH to 4096 to make
the search more aggressively for a possible better victim. Since
it also applies to victim selection for SSR, it will likely improve
the SSR efficiency as well.
The test case is simple. It creates as many files until the disk full.
The size for each file is 32KB. Then it writes as many as 100000
records of 4KB size to random offsets of random files in sync mode.
The testing was done on a 2GB partition of a SDHC card. Let's see the
test result of f2fs without and with the patch.
---------------------------------------
2GB partition, SDHC
create 52023 files of size 32768 bytes
random re-write 100000 records of 4KB
---------------------------------------
| file creation (s) | rewrite time (s) | gc count | gc garbage blocks |
[no patch] 341 4227 1174 174840
[patched] 324 2958 645 106682
It's obvious that, with the patch, f2fs finishes the test in 20+% less
time than without the patch. And internally it does much less gc with
higher efficiency than before.
Since the performance improvement is related to gc, it might not be so
obvious for other tests that do not trigger gc as often as this one (
This is because f2fs selects dirty segments for SSR use most of the
time when free space is in shortage). The well-known iozone test tool
was not used for benchmarking the patch becuase it seems do not have
a test case that performs random re-write on a full disk.
This patch is the revised version based on the suggestion from
Jaegeuk Kim.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: suggested simpler solution]
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 12:45:26 +08:00
|
|
|
if (nsearched++ >= p.max_search) {
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
sbi->last_victim[p.gc_mode] = segno;
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
if (p.min_segno != NULL_SEGNO) {
|
2013-06-01 15:20:26 +08:00
|
|
|
got_it:
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (p.alloc_mode == LFS) {
|
2013-03-31 12:26:03 +08:00
|
|
|
secno = GET_SECNO(sbi, p.min_segno);
|
|
|
|
|
if (gc_type == FG_GC)
|
|
|
|
|
sbi->cur_victim_sec = secno;
|
|
|
|
|
else
|
|
|
|
|
set_bit(secno, dirty_i->victim_secmap);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
2013-03-31 12:26:03 +08:00
|
|
|
*result = (p.min_segno / p.ofs_unit) * p.ofs_unit;
|
2013-04-23 15:42:53 +08:00
|
|
|
|
|
|
|
|
trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
|
|
|
|
|
sbi->cur_victim_sec,
|
|
|
|
|
prefree_segments(sbi), free_segments(sbi));
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
mutex_unlock(&dirty_i->seglist_lock);
|
|
|
|
|
|
|
|
|
|
return (p.min_segno == NULL_SEGNO) ? 0 : 1;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static const struct victim_selection default_v_ops = {
|
|
|
|
|
.get_victim = get_victim_by_default,
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
static struct inode *find_gc_inode(nid_t ino, struct list_head *ilist)
|
|
|
|
|
{
|
|
|
|
|
struct inode_entry *ie;
|
|
|
|
|
|
2013-06-20 17:52:39 +08:00
|
|
|
list_for_each_entry(ie, ilist, list)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (ie->inode->i_ino == ino)
|
|
|
|
|
return ie->inode;
|
|
|
|
|
return NULL;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void add_gc_inode(struct inode *inode, struct list_head *ilist)
|
|
|
|
|
{
|
2013-06-20 17:52:39 +08:00
|
|
|
struct inode_entry *new_ie;
|
|
|
|
|
|
|
|
|
|
if (inode == find_gc_inode(inode->i_ino, ilist)) {
|
|
|
|
|
iput(inode);
|
|
|
|
|
return;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
2013-10-22 14:52:26 +08:00
|
|
|
|
|
|
|
|
new_ie = f2fs_kmem_cache_alloc(winode_slab, GFP_NOFS);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
new_ie->inode = inode;
|
|
|
|
|
list_add_tail(&new_ie->list, ilist);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void put_gc_inode(struct list_head *ilist)
|
|
|
|
|
{
|
|
|
|
|
struct inode_entry *ie, *next_ie;
|
|
|
|
|
list_for_each_entry_safe(ie, next_ie, ilist, list) {
|
|
|
|
|
iput(ie->inode);
|
|
|
|
|
list_del(&ie->list);
|
|
|
|
|
kmem_cache_free(winode_slab, ie);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int check_valid_map(struct f2fs_sb_info *sbi,
|
|
|
|
|
unsigned int segno, int offset)
|
|
|
|
|
{
|
|
|
|
|
struct sit_info *sit_i = SIT_I(sbi);
|
|
|
|
|
struct seg_entry *sentry;
|
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
|
|
mutex_lock(&sit_i->sentry_lock);
|
|
|
|
|
sentry = get_seg_entry(sbi, segno);
|
|
|
|
|
ret = f2fs_test_bit(offset, sentry->cur_valid_map);
|
|
|
|
|
mutex_unlock(&sit_i->sentry_lock);
|
2013-02-04 14:11:17 +08:00
|
|
|
return ret;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
2012-11-29 12:28:09 +08:00
|
|
|
/*
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
* This function compares node address got in summary with that in NAT.
|
|
|
|
|
* On validity, copy that node with cold status, otherwise (invalid node)
|
|
|
|
|
* ignore that.
|
|
|
|
|
*/
|
2013-02-04 14:11:17 +08:00
|
|
|
static void gc_node_segment(struct f2fs_sb_info *sbi,
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
struct f2fs_summary *sum, unsigned int segno, int gc_type)
|
|
|
|
|
{
|
|
|
|
|
bool initial = true;
|
|
|
|
|
struct f2fs_summary *entry;
|
|
|
|
|
int off;
|
|
|
|
|
|
|
|
|
|
next_step:
|
|
|
|
|
entry = sum;
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
|
|
|
|
|
nid_t nid = le32_to_cpu(entry->nid);
|
|
|
|
|
struct page *node_page;
|
|
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
/* stop BG_GC if there is not enough free sections. */
|
|
|
|
|
if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
|
|
|
|
|
return;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
if (check_valid_map(sbi, segno, off) == 0)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (initial) {
|
|
|
|
|
ra_node_page(sbi, nid);
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
node_page = get_node_page(sbi, nid);
|
|
|
|
|
if (IS_ERR(node_page))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
/* set page dirty and write it */
|
2013-03-31 12:49:18 +08:00
|
|
|
if (gc_type == FG_GC) {
|
2014-01-10 15:26:14 +08:00
|
|
|
f2fs_wait_on_page_writeback(node_page, NODE);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
set_page_dirty(node_page);
|
2013-03-31 12:49:18 +08:00
|
|
|
} else {
|
|
|
|
|
if (!PageWriteback(node_page))
|
|
|
|
|
set_page_dirty(node_page);
|
|
|
|
|
}
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
f2fs_put_page(node_page, 1);
|
|
|
|
|
stat_inc_node_blk_count(sbi, 1);
|
|
|
|
|
}
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (initial) {
|
|
|
|
|
initial = false;
|
|
|
|
|
goto next_step;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (gc_type == FG_GC) {
|
|
|
|
|
struct writeback_control wbc = {
|
|
|
|
|
.sync_mode = WB_SYNC_ALL,
|
|
|
|
|
.nr_to_write = LONG_MAX,
|
|
|
|
|
.for_reclaim = 0,
|
|
|
|
|
};
|
|
|
|
|
sync_node_pages(sbi, 0, &wbc);
|
2013-03-31 12:49:18 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* In the case of FG_GC, it'd be better to reclaim this victim
|
|
|
|
|
* completely.
|
|
|
|
|
*/
|
|
|
|
|
if (get_valid_blocks(sbi, segno, 1) != 0)
|
|
|
|
|
goto next_step;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
2012-11-29 12:28:09 +08:00
|
|
|
/*
|
2013-01-21 16:34:21 +08:00
|
|
|
* Calculate start block index indicating the given node offset.
|
|
|
|
|
* Be careful, caller should give this node offset only indicating direct node
|
|
|
|
|
* blocks. If any node offsets, which point the other types of node blocks such
|
|
|
|
|
* as indirect or double indirect node blocks, are given, it must be a caller's
|
|
|
|
|
* bug.
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
*/
|
2013-08-12 20:08:03 +08:00
|
|
|
block_t start_bidx_of_node(unsigned int node_ofs, struct f2fs_inode_info *fi)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
{
|
2012-12-26 11:03:22 +08:00
|
|
|
unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4;
|
|
|
|
|
unsigned int bidx;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2012-12-26 11:03:22 +08:00
|
|
|
if (node_ofs == 0)
|
|
|
|
|
return 0;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2012-12-26 11:03:22 +08:00
|
|
|
if (node_ofs <= 2) {
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
bidx = node_ofs - 1;
|
|
|
|
|
} else if (node_ofs <= indirect_blks) {
|
2012-12-26 11:03:22 +08:00
|
|
|
int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
bidx = node_ofs - 2 - dec;
|
|
|
|
|
} else {
|
2012-12-26 11:03:22 +08:00
|
|
|
int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
bidx = node_ofs - 5 - dec;
|
|
|
|
|
}
|
2013-08-12 20:08:03 +08:00
|
|
|
return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(fi);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
|
|
|
|
|
struct node_info *dni, block_t blkaddr, unsigned int *nofs)
|
|
|
|
|
{
|
|
|
|
|
struct page *node_page;
|
|
|
|
|
nid_t nid;
|
|
|
|
|
unsigned int ofs_in_node;
|
|
|
|
|
block_t source_blkaddr;
|
|
|
|
|
|
|
|
|
|
nid = le32_to_cpu(sum->nid);
|
|
|
|
|
ofs_in_node = le16_to_cpu(sum->ofs_in_node);
|
|
|
|
|
|
|
|
|
|
node_page = get_node_page(sbi, nid);
|
|
|
|
|
if (IS_ERR(node_page))
|
2013-02-04 14:11:17 +08:00
|
|
|
return 0;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
get_node_info(sbi, nid, dni);
|
|
|
|
|
|
|
|
|
|
if (sum->version != dni->version) {
|
|
|
|
|
f2fs_put_page(node_page, 1);
|
2013-02-04 14:11:17 +08:00
|
|
|
return 0;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
*nofs = ofs_of_node(node_page);
|
|
|
|
|
source_blkaddr = datablock_addr(node_page, ofs_in_node);
|
|
|
|
|
f2fs_put_page(node_page, 1);
|
|
|
|
|
|
|
|
|
|
if (source_blkaddr != blkaddr)
|
2013-02-04 14:11:17 +08:00
|
|
|
return 0;
|
|
|
|
|
return 1;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void move_data_page(struct inode *inode, struct page *page, int gc_type)
|
|
|
|
|
{
|
2013-12-11 12:54:01 +08:00
|
|
|
struct f2fs_io_info fio = {
|
|
|
|
|
.type = DATA,
|
|
|
|
|
.rw = WRITE_SYNC,
|
2013-12-09 16:09:00 +08:00
|
|
|
};
|
|
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (gc_type == BG_GC) {
|
2013-03-31 12:49:18 +08:00
|
|
|
if (PageWriteback(page))
|
|
|
|
|
goto out;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
set_page_dirty(page);
|
|
|
|
|
set_cold_data(page);
|
|
|
|
|
} else {
|
|
|
|
|
struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
|
2013-03-31 12:49:18 +08:00
|
|
|
|
2014-01-10 15:26:14 +08:00
|
|
|
f2fs_wait_on_page_writeback(page, DATA);
|
2013-03-31 12:49:18 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (clear_page_dirty_for_io(page) &&
|
|
|
|
|
S_ISDIR(inode->i_mode)) {
|
|
|
|
|
dec_page_count(sbi, F2FS_DIRTY_DENTS);
|
|
|
|
|
inode_dec_dirty_dents(inode);
|
|
|
|
|
}
|
|
|
|
|
set_cold_data(page);
|
2013-12-11 12:54:01 +08:00
|
|
|
do_write_data_page(page, &fio);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
clear_cold_data(page);
|
|
|
|
|
}
|
|
|
|
|
out:
|
|
|
|
|
f2fs_put_page(page, 1);
|
|
|
|
|
}
|
|
|
|
|
|
2012-11-29 12:28:09 +08:00
|
|
|
/*
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
* This function tries to get parent node of victim data block, and identifies
|
|
|
|
|
* data block validity. If the block is valid, copy that with cold status and
|
|
|
|
|
* modify parent node.
|
|
|
|
|
* If the parent node is not valid or the data block address is different,
|
|
|
|
|
* the victim data block is ignored.
|
|
|
|
|
*/
|
2013-02-04 14:11:17 +08:00
|
|
|
static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
struct list_head *ilist, unsigned int segno, int gc_type)
|
|
|
|
|
{
|
|
|
|
|
struct super_block *sb = sbi->sb;
|
|
|
|
|
struct f2fs_summary *entry;
|
|
|
|
|
block_t start_addr;
|
2013-02-04 14:11:17 +08:00
|
|
|
int off;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
int phase = 0;
|
|
|
|
|
|
|
|
|
|
start_addr = START_BLOCK(sbi, segno);
|
|
|
|
|
|
|
|
|
|
next_step:
|
|
|
|
|
entry = sum;
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
|
|
|
|
|
struct page *data_page;
|
|
|
|
|
struct inode *inode;
|
|
|
|
|
struct node_info dni; /* dnode info for the data */
|
|
|
|
|
unsigned int ofs_in_node, nofs;
|
|
|
|
|
block_t start_bidx;
|
|
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
/* stop BG_GC if there is not enough free sections. */
|
|
|
|
|
if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
|
|
|
|
|
return;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
if (check_valid_map(sbi, segno, off) == 0)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (phase == 0) {
|
|
|
|
|
ra_node_page(sbi, le32_to_cpu(entry->nid));
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Get an inode by ino with checking validity */
|
2013-02-04 14:11:17 +08:00
|
|
|
if (check_dnode(sbi, entry, &dni, start_addr + off, &nofs) == 0)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (phase == 1) {
|
|
|
|
|
ra_node_page(sbi, dni.ino);
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
ofs_in_node = le16_to_cpu(entry->ofs_in_node);
|
|
|
|
|
|
|
|
|
|
if (phase == 2) {
|
f2fs: avoid balanc_fs during evict_inode
1. Background
Previously, if f2fs tries to move data blocks of an *evicting* inode during the
cleaning process, it stops the process incompletely and then restarts the whole
process, since it needs a locked inode to grab victim data pages in its address
space. In order to get a locked inode, iget_locked() by f2fs_iget() is normally
used, but, it waits if the inode is on freeing.
So, here is a deadlock scenario.
1. f2fs_evict_inode() <- inode "A"
2. f2fs_balance_fs()
3. f2fs_gc()
4. gc_data_segment()
5. f2fs_iget() <- inode "A" too!
If step #1 and #5 treat a same inode "A", step #5 would fall into deadlock since
the inode "A" is on freeing. In order to resolve this, f2fs_iget_nowait() which
skips __wait_on_freeing_inode() was introduced in step #5, and stops f2fs_gc()
to complete f2fs_evict_inode().
1. f2fs_evict_inode() <- inode "A"
2. f2fs_balance_fs()
3. f2fs_gc()
4. gc_data_segment()
5. f2fs_iget_nowait() <- inode "A", then stop f2fs_gc() w/ -ENOENT
2. Problem and Solution
In the above scenario, however, f2fs cannot finish f2fs_evict_inode() only if:
o there are not enough free sections, and
o f2fs_gc() tries to move data blocks of the *evicting* inode repeatedly.
So, the final solution is to use f2fs_iget() and remove f2fs_balance_fs() in
f2fs_evict_inode().
The f2fs_evict_inode() actually truncates all the data and node blocks, which
means that it doesn't produce any dirty node pages accordingly.
So, we don't need to do f2fs_balance_fs() in practical.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-31 14:36:04 +08:00
|
|
|
inode = f2fs_iget(sb, dni.ino);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (IS_ERR(inode))
|
|
|
|
|
continue;
|
|
|
|
|
|
2013-08-12 20:08:03 +08:00
|
|
|
start_bidx = start_bidx_of_node(nofs, F2FS_I(inode));
|
|
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
data_page = find_data_page(inode,
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
start_bidx + ofs_in_node, false);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (IS_ERR(data_page))
|
|
|
|
|
goto next_iput;
|
|
|
|
|
|
|
|
|
|
f2fs_put_page(data_page, 0);
|
|
|
|
|
add_gc_inode(inode, ilist);
|
|
|
|
|
} else {
|
|
|
|
|
inode = find_gc_inode(dni.ino, ilist);
|
|
|
|
|
if (inode) {
|
2013-08-12 20:08:03 +08:00
|
|
|
start_bidx = start_bidx_of_node(nofs,
|
|
|
|
|
F2FS_I(inode));
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
data_page = get_lock_data_page(inode,
|
|
|
|
|
start_bidx + ofs_in_node);
|
|
|
|
|
if (IS_ERR(data_page))
|
|
|
|
|
continue;
|
|
|
|
|
move_data_page(inode, data_page, gc_type);
|
|
|
|
|
stat_inc_data_blk_count(sbi, 1);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
continue;
|
|
|
|
|
next_iput:
|
|
|
|
|
iput(inode);
|
|
|
|
|
}
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
if (++phase < 4)
|
|
|
|
|
goto next_step;
|
2013-02-04 14:11:17 +08:00
|
|
|
|
2013-03-31 12:49:18 +08:00
|
|
|
if (gc_type == FG_GC) {
|
2013-12-11 12:54:01 +08:00
|
|
|
f2fs_submit_merged_bio(sbi, DATA, WRITE);
|
2013-03-31 12:49:18 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* In the case of FG_GC, it'd be better to reclaim this victim
|
|
|
|
|
* completely.
|
|
|
|
|
*/
|
|
|
|
|
if (get_valid_blocks(sbi, segno, 1) != 0) {
|
|
|
|
|
phase = 2;
|
|
|
|
|
goto next_step;
|
|
|
|
|
}
|
|
|
|
|
}
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim,
|
|
|
|
|
int gc_type, int type)
|
|
|
|
|
{
|
|
|
|
|
struct sit_info *sit_i = SIT_I(sbi);
|
|
|
|
|
int ret;
|
|
|
|
|
mutex_lock(&sit_i->sentry_lock);
|
|
|
|
|
ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, type, LFS);
|
|
|
|
|
mutex_unlock(&sit_i->sentry_lock);
|
|
|
|
|
return ret;
|
|
|
|
|
}
|
|
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
struct list_head *ilist, int gc_type)
|
|
|
|
|
{
|
|
|
|
|
struct page *sum_page;
|
|
|
|
|
struct f2fs_summary_block *sum;
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
struct blk_plug plug;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
/* read segment summary of victim */
|
|
|
|
|
sum_page = get_sum_page(sbi, segno);
|
|
|
|
|
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
blk_start_plug(&plug);
|
|
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
sum = page_address(sum_page);
|
|
|
|
|
|
|
|
|
|
switch (GET_SUM_TYPE((&sum->footer))) {
|
|
|
|
|
case SUM_TYPE_NODE:
|
2013-02-04 14:11:17 +08:00
|
|
|
gc_node_segment(sbi, sum->entries, segno, gc_type);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
break;
|
|
|
|
|
case SUM_TYPE_DATA:
|
2013-02-04 14:11:17 +08:00
|
|
|
gc_data_segment(sbi, sum->entries, ilist, segno, gc_type);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
break;
|
|
|
|
|
}
|
f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.
...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...
However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.
...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...
Note that this issue should be addressed in checkpoint, and some readahead
flows too.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-24 12:19:56 +08:00
|
|
|
blk_finish_plug(&plug);
|
|
|
|
|
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)));
|
|
|
|
|
stat_inc_call_count(sbi->stat_info);
|
|
|
|
|
|
2013-04-01 07:32:21 +08:00
|
|
|
f2fs_put_page(sum_page, 1);
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
2013-01-03 16:55:52 +08:00
|
|
|
int f2fs_gc(struct f2fs_sb_info *sbi)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
{
|
|
|
|
|
struct list_head ilist;
|
2013-01-03 16:55:52 +08:00
|
|
|
unsigned int segno, i;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
int gc_type = BG_GC;
|
2013-02-04 14:11:17 +08:00
|
|
|
int nfree = 0;
|
|
|
|
|
int ret = -1;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
|
|
|
|
INIT_LIST_HEAD(&ilist);
|
|
|
|
|
gc_more:
|
2013-12-06 14:00:58 +08:00
|
|
|
if (unlikely(!(sbi->sb->s_flags & MS_ACTIVE)))
|
2013-01-03 16:55:52 +08:00
|
|
|
goto stop;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-04-08 15:01:00 +08:00
|
|
|
if (gc_type == BG_GC && has_not_enough_free_secs(sbi, nfree)) {
|
2013-01-03 16:55:52 +08:00
|
|
|
gc_type = FG_GC;
|
2013-04-08 15:01:00 +08:00
|
|
|
write_checkpoint(sbi, false);
|
|
|
|
|
}
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-01-03 16:55:52 +08:00
|
|
|
if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE))
|
|
|
|
|
goto stop;
|
2013-02-04 14:11:17 +08:00
|
|
|
ret = 0;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
|
2013-02-04 14:11:17 +08:00
|
|
|
for (i = 0; i < sbi->segs_per_sec; i++)
|
|
|
|
|
do_garbage_collect(sbi, segno + i, &ilist, gc_type);
|
|
|
|
|
|
2013-03-31 12:26:03 +08:00
|
|
|
if (gc_type == FG_GC) {
|
|
|
|
|
sbi->cur_victim_sec = NULL_SEGNO;
|
2013-02-04 14:11:17 +08:00
|
|
|
nfree++;
|
2013-03-31 12:26:03 +08:00
|
|
|
WARN_ON(get_valid_blocks(sbi, segno, sbi->segs_per_sec));
|
|
|
|
|
}
|
2013-02-04 14:11:17 +08:00
|
|
|
|
|
|
|
|
if (has_not_enough_free_secs(sbi, nfree))
|
|
|
|
|
goto gc_more;
|
|
|
|
|
|
|
|
|
|
if (gc_type == FG_GC)
|
|
|
|
|
write_checkpoint(sbi, false);
|
2013-01-03 16:55:52 +08:00
|
|
|
stop:
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
mutex_unlock(&sbi->gc_mutex);
|
|
|
|
|
|
|
|
|
|
put_gc_inode(&ilist);
|
2013-02-04 14:11:17 +08:00
|
|
|
return ret;
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void build_gc_manager(struct f2fs_sb_info *sbi)
|
|
|
|
|
{
|
|
|
|
|
DIRTY_I(sbi)->v_ops = &default_v_ops;
|
|
|
|
|
}
|
|
|
|
|
|
2013-01-16 23:08:30 +08:00
|
|
|
int __init create_gc_caches(void)
|
f2fs: add garbage collection functions
This adds on-demand and background cleaning functions.
- The basic background cleaning policy is trying to do cleaning jobs as much as
possible whenever the system is idle. Once the background cleaning is done,
the cleaner sleeps an amount of time not to interfere with VFS calls. The time
is dynamically adjusted according to the status of whole segments, which is
decreased when the following conditions are satisfied.
. GC is not conducted currently, and
. IO subsystem is idle by checking the number of requets in bdev's request
list, and
. There are enough dirty segments.
Otherwise, the time is increased incrementally until to the maximum time.
Note that, min and max times are 10 secs and 30 secs by default.
- F2FS adopts a default victim selection policy where background cleaning uses
a cost-benefit algorithm, while on-demand cleaning uses a greedy algorithm.
- The method of moving data during the cleaning is slightly different between
background and on-demand cleaning schemes. In the case of background cleaning,
F2FS loads the data, and marks them as dirty. Then, F2FS expects that the data
will be moved by flusher or VM. In the case of on-demand cleaning, F2FS should
move the data right away.
- In order to identify valid blocks in a victim segment, F2FS scans the bitmap
of the segment managed as an SIT entry.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-11-02 16:13:01 +08:00
|
|
|
{
|
|
|
|
|
winode_slab = f2fs_kmem_cache_create("f2fs_gc_inodes",
|
|
|
|
|
sizeof(struct inode_entry), NULL);
|
|
|
|
|
if (!winode_slab)
|
|
|
|
|
return -ENOMEM;
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void destroy_gc_caches(void)
|
|
|
|
|
{
|
|
|
|
|
kmem_cache_destroy(winode_slab);
|
|
|
|
|
}
|