• Programmer Belch
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    21 year ago

    I think the -j also compresses with bzip2 but I’m not sure if this is defined behavior or just a shortcut

    • aard
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      31 year ago

      Yes, but I’m asking you to use pbzip. bzip at best utilizes one core, both for packing and unpacking. pbzip uses as many cores as IO bandwith allows - with standard SATA SSDs that’s typically around 30.

      pbzip can only utilize multiple cores if the archive was created with it as well.

        • Programmer Belch
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          31 year ago

          I’ve searched for it and xz also doesn’t use multithreading by default, you can change the program tar uses to compress by passing the -I option. For xz using all possible CPU threads:

          tar -cv -I 'xz -6 -T0' -f archive.tar.xz [list of directories]

          The number indicates the compression ratio, the higher the number, the more compressed the archive will be but it will cost more in terms of memory and processing time

          • TheSaneWriter
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            21 year ago

            Thanks for answering your own question, this is useful information.

    • @tony@lemmy.hoyle.me.uk
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      31 year ago

      There’s nothing technically wrong with using xjf rather than xzf, but it’ll bite you if you ever use a non-linux platform as it’s a GNU extension. I’m not even sure busybox tar supports it.