[thangngoc89]

Wow. Thank you for making this. I'm frequently have to zip and unzip ~100GB of zip archive and I have to waste 10 minutes of waiting on a fast NVMe and 32 cores workstation. I know about ZSTD or pigz but the format must be zip.

[acqq]

7-Zip by Igor Pavlov can create zip files, has multi-threading and in my small test, comparing with the "pzip", was both as fast in "real" time and produced smaller file (while using similar amount of CPU but differently distributed between user and sys).

https://www.7-zip.org/download.html

Also, in my example the compression level of Info-Zip that best matched the one in pzip was -3 This can, of course, depend on the set.

    ~/c/measure_pzip$ time 7z -tzip -mx1 a a7.zip /usr/lib/apache2/*

    7-Zip (z) 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
     64-bit locale=en_US.UTF-8 Threads:3 OPEN_MAX:1024, ASM

    ...

    real 0m0,074s
    user 0m0,121s
    sys 0m0,014s
    ~/c/measure_pzip$ time ./pzip a-p.zip /usr/lib/apache2/*

    real 0m0,073s
    user 0m0,097s
    sys 0m0,038s
    ~/c/measure_pzip$ time zip -3 -r a-zip.zip /usr/lib/apache2/ >/dev/null

    real 0m0,118s
    user 0m0,114s
    sys 0m0,004s

    ~/c/measure_pzip$ ls -l a*.zip | ./my2
    1576511  a7.zip
    1619733  a-p.zip
    1613607  a-zip.zip

[acqq]

Testing with 100 MB set from mattmahoney.net and relatively comparable sizes pzip is twice as fast as the previously mentioned Pavlov's 7z, that's clearly useful for those who need the fastest possible creation of a "classic" zip with compressed files, when lower compression ratio (1.6 MB bigger compressed file when compressing 100 MB set, compared to 7z) is acceptable.

    $ time zip -2 -r a-zip.zip 100mb/ >/dev/null
    real user sys: 2,1 1,8 0,1 
    $ time 7z -tzip -mx=1 a a-7z-1.zip 100mb/ >/dev/null
    real user sys: 1,0 2,7 0,0 
    $ time ../pzip a-pzip.zip 100mb/ >/dev/null
    real user sys: 0,5 1,0 0,1 
    $ L a
    48197707 a-7z-1.zip
    49921626 a-pzip.zip
    49553097 a-zip.zip

If the "classic" (i.e. the goal to unpack the archive using older programs) compatibility is not important, it could be interesting to consider that at least since 2020 zstd is officially a "standard" method for ZIP files too, allowing even faster compression speed for the same compression size targets.

    93 - Zstandard (zstd) Compression 

https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.9.TX...

I'm aware that there are some attempts of modifications of 7zip to allow using that method in ZIP files, but I don't know more than that:

https://github.com/mcmilk/7-Zip-zstd

https://github.com/mcmilk/7-Zip-zstd/issues/132

https://github.com/libarchive/libarchive/issues/1403

If ZIP target format is not a condition, here's the speed of using zstd on tar for the same input and approximately the same resulting size:

    time tar -c 100mb | zstd -2 -o a.tar.zst 2>/dev/null
    real user sys: 0,4 0,4 0,1 
    48585639 a.tar.zst

[mxmlnkn]

Is that by chance a public dataset? I would like to do some benchmarks with large non-synthetic zip archives.

[thangngoc89]

Here you go it’s ~200GB https://www.kaggle.com/c/rsna-intracranial-hemorrhage-detect...