Commit Graph

3 Commits

Author SHA1 Message Date
Philippe Liard 93e72b3c61 squashfs: migrate from ll_rw_block usage to BIO
ll_rw_block() function has been deprecated in favor of BIO which appears
to come with large performance improvements.

This patch decreases boot time by close to 40% when using squashfs for
the root file-system.  This is observed at least in the context of
starting an Android VM on Chrome OS using crosvm.  The patch was tested
on 4.19 as well as master.

This patch is largely based on Adrien Schildknecht's patch that was
originally sent as https://lkml.org/lkml/2017/9/22/814 though with some
significant changes and simplifications while also taking Phillip
Lougher's feedback into account, around preserving support for
FILE_CACHE in particular.

[akpm@linux-foundation.org: fix build error reported by Randy]
  Link: http://lkml.kernel.org/r/319997c2-5fc8-f889-2ea3-d913308a7c1f@infradead.org
Signed-off-by: Philippe Liard <pliard@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Adrien Schildknecht <adrien+dev@schischi.me>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Daniel Rosenberg <drosen@google.com>
Link: https://chromium.googlesource.com/chromiumos/platform/crosvm
Link: http://lkml.kernel.org/r/20191106074238.186023-1-pliard@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:05 -07:00
Thomas Gleixner 3e0a4e8580 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version this program is distributed in the hope that it will
  be useful but without any warranty without even the implied warranty
  of merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.032047323@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:02 +02:00
Sean Purcell 87bf54bb43 squashfs: Add zstd support
Add zstd compression and decompression support to SquashFS. zstd is a
great fit for SquashFS because it can compress at ratios approaching xz,
while decompressing twice as fast as zlib. For SquashFS in particular,
it can decompress as fast as lzo and lz4. It also has the flexibility
to turn down the compression ratio for faster compression times.

The compression benchmark is run on the file tree from the SquashFS archive
found in ubuntu-16.10-desktop-amd64.iso [1]. It uses `mksquashfs` with the
default block size (128 KB) and and various compression algorithms/levels.
xz and zstd are also benchmarked with 256 KB blocks. The decompression
benchmark times how long it takes to `tar` the file tree into `/dev/null`.
See the benchmark file in the upstream zstd source repository located under
`contrib/linux-kernel/squashfs-benchmark.sh` [2] for details.

I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM.
The VM is running on a MacBook Pro with a 3.1 GHz Intel Core i7 processor,
16 GB of RAM, and a SSD.

| Method         | Ratio | Compression MB/s | Decompression MB/s |
|----------------|-------|------------------|--------------------|
| gzip           |  2.92 |               15 |                128 |
| lzo            |  2.64 |              9.5 |                217 |
| lz4            |  2.12 |               94 |                218 |
| xz             |  3.43 |              5.5 |                 35 |
| xz 256 KB      |  3.53 |              5.4 |                 40 |
| zstd 1         |  2.71 |               96 |                210 |
| zstd 5         |  2.93 |               69 |                198 |
| zstd 10        |  3.01 |               41 |                225 |
| zstd 15        |  3.13 |             11.4 |                224 |
| zstd 16 256 KB |  3.24 |              8.1 |                210 |

This patch was written by Sean Purcell <me@seanp.xyz>, but I will be
taking over the submission process.

[1] http://releases.ubuntu.com/16.10/
[2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/squashfs-benchmark.sh

zstd source repository: https://github.com/facebook/zstd

Signed-off-by: Sean Purcell <me@seanp.xyz>
Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: Phillip Lougher <phillip@squashfs.org.uk>
2017-09-08 19:33:25 -07:00