Re: Linux Kernel Source Compression

On Sunday 21 May 2006 23:22, Sam Vilain wrote:
[snip]
Interesting. Googling a bit; from http://tukaani.org/lzma/benchmarks:

In terms of speed, gzip is the winner again. lzma comes right behind it
two to three times slower than gzip. bzip2 is a lot slower taking
usually two to six times more time than lzma, that is, four to twelve
times more than gzip. One interesting thing is that gzip and lzma
decompress the faster the smaller the compressed size is, while bzip2
gets slower when the compression ratio gets better.
[...]
neither bzip2 nor lzma can compete with gzip in terms of speed or memory
usage.

Also this:

"lzmash -8" and "lzmash -9" require lots of memory and are practical
only on newer computers; the files compressed with them are probably a
pain to decompress on systems with less than 32 MB or 64 MB of memory.
[...]
The files compressed with the default "lzmash -7" can still be
decompressed, even on machines with only 16 MB of RAM

Interesting info. I agree that LZMA is not a replacement for gzip/zlib,
because gzip is extremely size/time efficient.

However, as noted in another thread, it is almost certainly a viable
replacement for bzip2, since people that use bzip2 are generally interested
in a size optimisation, not a compression speed one, and even if compression
speed is relevant, LZMA's options scale to be approximately as good (or as
bad??) as bzip2.

This is all fairly academic. I think the issue still boils down to widespread
adoption; bzip2 took a while to get off the ground, people don't like messing
with new formats, and distributors have to pick up the tools.

I think kernel.org switching formats would be one of the last things that
could, or indeed should, happen.

--
Cheers,
Alistair.

Third year Computer Science undergraduate.
1F2 55 South Clerk Street, Edinburgh, UK.
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