• Nick Terrell's avatar
    zstd: import usptream v1.5.2 · 2aa14b1a
    Nick Terrell authored
    Updates the kernel's zstd library to v1.5.2, the latest zstd release.
    The upstream tag it is updated to is `v1.5.2-kernel`, which contains
    several cherry-picked commits on top of the v1.5.2 release which are
    required for the kernel update. I will create this tag once the PR is
    ready to merge, until then reference the temporary upstream branch
    `v1.5.2-kernel-cherrypicks`.
    
    I plan to submit this patch as part of the v6.2 merge window.
    
    I've done basic build testing & testing on x86-64, i386, and aarch64.
    I'm merging these patches into my `zstd-next` branch, which is pulled
    into `linux-next` for further testing.
    
    I've benchmarked BtrFS with zstd compression on a x86-64 machine, and
    saw these results. Decompression speed is a small win across the board.
    The lower compression levels 1-4 see both compression speed and
    compression ratio wins. The higher compression levels see a small
    compression speed loss and about neutral ratio. I expect the lower
    compression levels to be used much more heavily than the high
    compression levels, so this should be a net win.
    
    Level	CTime	DTime	Ratio
    1	-2.95%	-1.1%	-0.7%
    3	-3.5%	-1.2%	-0.5%
    5	+3.7%	-1.0%	+0.0%
    7	+3.2%	-0.9%	+0.0%
    9	-4.3%	-0.8%	+0.1%
    Signed-off-by: default avatarNick Terrell <terrelln@fb.com>
    2aa14b1a
zstd_decompress_internal.h 9.13 KB