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I disagree with your assessment. I'm aware of xz and use it when file size is paramount -- which, by the way, is almost never. Most of the time, I'm willing to give up a few megabytes in order to save time, and in my tests pbzip2 crushed xz by a factor of ten when it comes to speed.

Why not use parallelized versions of xz such as pxz or pixz? Because pre-built pxz/pixz packages are nearly non-existent. When that changes, I'll consider switching formats.

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Remember that compressors, including xz, support multiple compression levels. The default level for xz is 6, which is perhaps too far on the small-but-slow side. Levels 2 and lower tend to give similar compression levels to bzip2, and are considerably faster.

Also, note that decompressing bzip2 is very slow, xz usually beats it by a factor of two or more.

I agree that the default level (6) for xz probably errs too much on favoring file size over speed. My tests with compression levels 1-2 do indeed show modestly improved size and speed performance relative to single-threaded bzip2.

The fact remains, however, that I can't seem to find a simple way to install a parallelized version of xz. Perhaps I'll post an issue in the Github issue tracker for pixz and see if we can't resolve that. :)

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