Am 14.06.22 um 13:28 schrieb Johannes Schindelin: > > By the way, the main reason why I did not work more is that in > http://madler.net/pipermail/zlib-devel_madler.net/2019-December/003308.html, > Mark Adler (the zlib maintainer) announced that... > >> [...] There are many well-tested performance improvements in zlib >> waiting in the wings that will be incorporated over the next several >> months. [...] > > This was in December 2019. And now it's June 2022 and I kind of wonder > whether those promised improvements will still come. > > In the meantime, however, a viable alternative seems to have cropped up: > https://github.com/zlib-ng/zlib-ng. Essentially, it looks as if it is what > zlib should have become after above-quoted announcement. > > In particular the CPU intrinsics support (think MMX, SSE2/3, etc) seem to > be very interesting and I would not be completely surprised if building > Git with your patches and linking against zlib-ng would paint a very > favorable picture not only in terms of CPU time but also in terms of > wallclock time. Sadly, I have not been able to set aside time to look into > that angle, but maybe I can peak your interest? I was unable to preload zlib-ng using DYLD_INSERT_LIBRARIES on macOS 12.4 so far. The included demo proggy looks impressive, though: $ hyperfine -w3 -L gzip gzip,../zlib-ng/minigzip "git -C ../linux archive --format=tar HEAD | {gzip} -c" Benchmark #1: git -C ../linux archive --format=tar HEAD | gzip -c Time (mean ± σ): 20.424 s ± 0.006 s [User: 23.964 s, System: 0.432 s] Range (min … max): 20.414 s … 20.434 s 10 runs Benchmark #2: git -C ../linux archive --format=tar HEAD | ../zlib-ng/minigzip -c Time (mean ± σ): 12.158 s ± 0.006 s [User: 13.908 s, System: 0.376 s] Range (min … max): 12.145 s … 12.166 s 10 runs Summary 'git -C ../linux archive --format=tar HEAD | ../zlib-ng/minigzip -c' ran 1.68 ± 0.00 times faster than 'git -C ../linux archive --format=tar HEAD | gzip -c'
