Re: [GIT PULL v2] zstd support (lib, btrfs, squashfs, nocrypto)

[Phillip Lougher <phillip.lougher@gmail.com>]

On Mon, Sep 11, 2017 at 8:24 PM, Chris Mason <clm@fb.com> wrote:
> Hi Linus,
>
> Nick Terrell's patch series to add zstd support to the kernel has been
> floating around for a while.  After talking with Dave Sterba, Herbert
> and Phillip, we decided to send the whole thing in as one pull request.

As the Squashfs maintainer I have ACKed the Squashfs patch, and I
confirm that I've agreed to have it included in this one pull request.

Phillip

>
> Herbert had asked about the crypto patch when we discussed the pull, but
> I didn't realize he really meant not-right-now.  I've rebased it out of
> this branch, and none of the other patches depended on it.
>
> I have things in my zstd-minimal branch:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs.git zstd-minimal
>
> There's a trivial conflict with the main btrfs pull from last week.
> Dave's pull deletes BTRFS_COMPRESS_LAST in fs/btrfs/compression.h, and
> I've put the sample resolution in a branch named zstd-4.14-merge.
>
> zstd is a big win in speed over zlib and in compression ratio over lzo,
> and the compression team here at FB has gotten great results using it in
> production.  Nick will continue to update the kernel side with new
> improvements from the open source zstd userland code.
>
> Nick has a number of benchmarks for the main zstd code in his lib/zstd
> commit:
>
> ============
> 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. I benchmarked using `silesia.tar` [3], which is
> 211,988,480 B large. Run the following commands for the benchmark:
>
>     sudo modprobe zstd_compress_test
>     sudo mknod zstd_compress_test c 245 0
>     sudo cp silesia.tar zstd_compress_test
>
> The time is reported by the time of the userland `cp`.
> The MB/s is computed with
>
>     1,536,217,008 B / time(buffer size, hash)
>
> which includes the time to copy from userland.
> The Adjusted MB/s is computed with
>
>     1,536,217,088 B / (time(buffer size, hash) - time(buffer size, none)).
>
> The memory reported is the amount of memory the compressor requests.
>
> | Method   | Size (B) | Time (s) | Ratio | MB/s    | Adj MB/s | Mem (MB) |
> |----------|----------|----------|-------|---------|----------|----------|
> | none     | 11988480 |    0.100 |     1 | 2119.88 |        - |        - |
> | zstd -1  | 73645762 |    1.044 | 2.878 |  203.05 |   224.56 |     1.23 |
> | zstd -3  | 66988878 |    1.761 | 3.165 |  120.38 |   127.63 |     2.47 |
> | zstd -5  | 65001259 |    2.563 | 3.261 |   82.71 |    86.07 |     2.86 |
> | zstd -10 | 60165346 |   13.242 | 3.523 |   16.01 |    16.13 |    13.22 |
> | zstd -15 | 58009756 |   47.601 | 3.654 |    4.45 |     4.46 |    21.61 |
> | zstd -19 | 54014593 |  102.835 | 3.925 |    2.06 |     2.06 |    60.15 |
> | zlib -1  | 77260026 |    2.895 | 2.744 |   73.23 |    75.85 |     0.27 |
> | zlib -3  | 72972206 |    4.116 | 2.905 |   51.50 |    52.79 |     0.27 |
> | zlib -6  | 68190360 |    9.633 | 3.109 |   22.01 |    22.24 |     0.27 |
> | zlib -9  | 67613382 |   22.554 | 3.135 |    9.40 |     9.44 |     0.27 |
>
> I benchmarked zstd decompression using the same method on the same machine.
> The benchmark file is located in the upstream zstd repo under
> `contrib/linux-kernel/zstd_decompress_test.c` [4]. The memory reported is
> the amount of memory required to decompress data compressed with the given
> compression level. If you know the maximum size of your input, you can
> reduce the memory usage of decompression irrespective of the compression
> level.
>
> | Method   | Time (s) | MB/s    | Adjusted MB/s | Memory (MB) |
> |----------|----------|---------|---------------|-------------|
> | none     |    0.025 | 8479.54 |             - |           - |
> | zstd -1  |    0.358 |  592.15 |        636.60 |        0.84 |
> | zstd -3  |    0.396 |  535.32 |        571.40 |        1.46 |
> | zstd -5  |    0.396 |  535.32 |        571.40 |        1.46 |
> | zstd -10 |    0.374 |  566.81 |        607.42 |        2.51 |
> | zstd -15 |    0.379 |  559.34 |        598.84 |        4.61 |
> | zstd -19 |    0.412 |  514.54 |        547.77 |        8.80 |
> | zlib -1  |    0.940 |  225.52 |        231.68 |        0.04 |
> | zlib -3  |    0.883 |  240.08 |        247.07 |        0.04 |
> | zlib -6  |    0.844 |  251.17 |        258.84 |        0.04 |
> | zlib -9  |    0.837 |  253.27 |        287.64 |        0.04 |
>
> =======================
>
> I ran a long series of tests and benchmarks on the btrfs side and
> the gains are very similar to the core benchmarks Nick ran.
>
> Nick Terrell (3) commits (+14222/-12):
>     btrfs: Add zstd support (+468/-12)
>     lib: Add zstd modules (+13014/-0)
>     lib: Add xxhash module (+740/-0)
>
> Sean Purcell (1) commits (+178/-0):
>     squashfs: Add zstd support
>
> Total: (4) commits (+14400/-12)
>
>  fs/btrfs/Kconfig           |    2 +
>  fs/btrfs/Makefile          |    2 +-
>  fs/btrfs/compression.c     |    1 +
>  fs/btrfs/compression.h     |    6 +-
>  fs/btrfs/ctree.h           |    1 +
>  fs/btrfs/disk-io.c         |    2 +
>  fs/btrfs/ioctl.c           |    6 +-
>  fs/btrfs/props.c           |    6 +
>  fs/btrfs/super.c           |   12 +-
>  fs/btrfs/sysfs.c           |    2 +
>  fs/btrfs/zstd.c            |  432 ++++++
>  fs/squashfs/Kconfig        |   14 +
>  fs/squashfs/Makefile       |    1 +
>  fs/squashfs/decompressor.c |    7 +
>  fs/squashfs/decompressor.h |    4 +
>  fs/squashfs/squashfs_fs.h  |    1 +
>  fs/squashfs/zstd_wrapper.c |  151 ++
>  include/linux/xxhash.h     |  236 +++
>  include/linux/zstd.h       | 1157 +++++++++++++++
>  include/uapi/linux/btrfs.h |    8 +-
>  lib/Kconfig                |   11 +
>  lib/Makefile               |    3 +
>  lib/xxhash.c               |  500 +++++++
>  lib/zstd/Makefile          |   18 +
>  lib/zstd/bitstream.h       |  374 +++++
>  lib/zstd/compress.c        | 3484 ++++++++++++++++++++++++++++++++++++++++++++
>  lib/zstd/decompress.c      | 2528 ++++++++++++++++++++++++++++++++
>  lib/zstd/entropy_common.c  |  243 +++
>  lib/zstd/error_private.h   |   53 +
>  lib/zstd/fse.h             |  575 ++++++++
>  lib/zstd/fse_compress.c    |  795 ++++++++++
>  lib/zstd/fse_decompress.c  |  332 +++++
>  lib/zstd/huf.h             |  212 +++
>  lib/zstd/huf_compress.c    |  770 ++++++++++
>  lib/zstd/huf_decompress.c  |  960 ++++++++++++
>  lib/zstd/mem.h             |  151 ++
>  lib/zstd/zstd_common.c     |   75 +
>  lib/zstd/zstd_internal.h   |  263 ++++
>  lib/zstd/zstd_opt.h        | 1014 +++++++++++++
>  39 files changed, 14400 insertions(+), 12 deletions(-)