F21 System Wide Change: lbzip2 as default bzip2 implementation

Zbigniew Jędrzejewski-Szmek zbyszek at in.waw.pl
Tue Apr 8 14:44:01 UTC 2014


On Fri, Apr 04, 2014 at 12:49:25PM -0400, Matthew Miller wrote:
> On Fri, Apr 04, 2014 at 04:15:59PM +0200, Mikolaj Izdebski wrote:
> > "lbzip2" was the fastest compressor and decompressor in all tests.
> > It the best command for interactive use.
> > 
> > "lbzip2 -u" always produced smallest files (even smaller than bzip2)
> > while consuming the least amount of resources (CPU power and memory).
> > This directly translates to lowest bills in cloud, which makes "lbzip2
> > -u" the best choice here.
> 
> But... the size difference in your test cases appear to be 0.1% and
> 0.02%. Am I reading that right? And, compressing linux-3.12.6.tar with xz
> instead of bzip2 gives a 15.6%, or with xz -9, 19.7%. Of course, that's very
> slow, and the other resource factors are important too. (And lbzip2 is
> impressively fast.)
I think that xz is orthogonal: bzip2 files are quite popular and gains
in decompression speed are useful, even if bzip2 isn't the compressor of choice.

OTOH, we could also replace xz with a multithreaded implementation
like pxz by default. In case of xz it would matter even more, since it
is generally slower. It would be great if somebody proposed a change like
that.

Zbyszek


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