Friday 16 September 2011

lrzip-0.607

It's been a while since lrzip received any attention while I got distracted by cgminer. However a bug report where there was an archive that was not decompressible drew my attention. After a run of debugging and testing (thanks Entil!) I tracked down the bug. The nice thing was the archives were actually all intact, it was purely on decompression that it could be a problem, and it was extremely rare for an archive to be made in this way. So I fixed the bug, updated the lzma library to the latest, added an lrzip bash completion script and a couple of other minor things and have released version 0.607.

lrzip on freshmeat
http://lrzip.kolivas.org
http://github.com/ckolivas/lrzip

Meanwhile Michael Blumenkrantz has been working on a liblrzip library for lrzip! That means once we finalise the format, you'll be able to compile in lrzip support into your applications, using functions like:

lrzip_compress(void *dest, unsigned long *dest_len, const void *source, unsigned long source_len)

This work is currently in the liblrzip branch on the github tree.

6 comments:

  1. Thanks CK. Something is off with the installation - it doesn't appear to honor my DESTDIR= switch in the final step. Can you confirm?

    http://pastebin.com/mTcsV88x

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  2. Yep, thanks :(

    Stupid autofoo magic. Oh well guess a .608 is warranted.

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  3. Still broken with the newest commit (installs $DESTDIR/$DESTDIR/$sysconfdir/bash_completion.d/lrzip). The following seems to work properly for me:

    completiondir = $(sysconfdir)/bash_completion.d
    completion_DATA = bash_completion.d/lrzip

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  4. Nice to see you having some time to do some work on lrzip. I was wondering, I read somewhere on this blog that the reason lrzip generally have a worse compression ratio with large files than say 7-zip is because it does some preprocessing on the data. So I was wondering is will there possibly be a way to turn this proprocessing off manually if one would want to, or is lrzip dependant on this?

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  5. No, it actually does better than 7zip now. There is a sweet spot for 7zip where it may be better between say 10 and 100MB, but after that lrzip usually wins on speed and/or size. If you enable the unlimited mode with -U it would be very rare to find anything that 7zip is better at. If you disable the preprocessing then it isn't lrzip any more, it's just lzma...

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  6. About bash completion, please don't remove it from the package. Simply don't install it, but leave it in there so distro package scripts can install it on their own.

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