hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

mm: speed up writeback ramp-up on clean systems 

We allow violation of bdi limits if there is a lot of room on the system.
Once we hit half the total limit we start enforcing bdi limits and bdi
ramp-up should happen.  Doing it this way avoids many small writeouts on an
otherwise idle system and should also speed up the ramp-up.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Peter Zijlstra 2007-11-14 16:59:15 -08:00 committed by Linus Torvalds
parent 546040dc48
commit 5fce25a9df
1 changed files with 17 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
mm/page-writeback.c
View File

@ -355,8 +355,8 @@ get_dirty_limits(long *pbackground, long *pdirty, long *pbdi_dirty,
*/ */
static void balance_dirty_pages(struct address_space *mapping) static void balance_dirty_pages(struct address_space *mapping)
{ {
long bdi_nr_reclaimable; long nr_reclaimable, bdi_nr_reclaimable;
long bdi_nr_writeback; long nr_writeback, bdi_nr_writeback;
long background_thresh; long background_thresh;
long dirty_thresh; long dirty_thresh;
long bdi_thresh; long bdi_thresh;
@ -376,11 +376,26 @@ static void balance_dirty_pages(struct address_space *mapping)
get_dirty_limits(&background_thresh, &dirty_thresh, get_dirty_limits(&background_thresh, &dirty_thresh,
&bdi_thresh, bdi); &bdi_thresh, bdi);
nr_reclaimable = global_page_state(NR_FILE_DIRTY) +
global_page_state(NR_UNSTABLE_NFS);
nr_writeback = global_page_state(NR_WRITEBACK);
bdi_nr_reclaimable = bdi_stat(bdi, BDI_RECLAIMABLE); bdi_nr_reclaimable = bdi_stat(bdi, BDI_RECLAIMABLE);
bdi_nr_writeback = bdi_stat(bdi, BDI_WRITEBACK); bdi_nr_writeback = bdi_stat(bdi, BDI_WRITEBACK);
if (bdi_nr_reclaimable + bdi_nr_writeback <= bdi_thresh) if (bdi_nr_reclaimable + bdi_nr_writeback <= bdi_thresh)
break; break;
/*
* Throttle it only when the background writeback cannot
* catch-up. This avoids (excessively) small writeouts
* when the bdi limits are ramping up.
*/
if (nr_reclaimable + nr_writeback <
(background_thresh + dirty_thresh) / 2)
break;
if (!bdi->dirty_exceeded) if (!bdi->dirty_exceeded)
bdi->dirty_exceeded = 1; bdi->dirty_exceeded = 1;