On 16/02/10 21:03, Jan de Groot wrote:
On Tue, 2010-02-16 at 11:21 +0100, Pierre Schmitz wrote:
Am Dienstag, 16. Februar 2010 08:51:50 schrieb Jan de Groot:
What's the compression rate used in your test? I've seen benchmarks for an older version of xz-utils (I think it was called lzma-utils). In that benchmark the most simple compression level was faster and smaller than gzip -9, and bzip2 was outperformed anyways.
I just used the default which should be -6.
Note that tighter compressions needs a bigger dictionary size when unpacking, which can be crap on low-memory systems.
Do you have numbers? We could do some testing in qemu with e.g. 128MB RAM etc.. Or maybe have a look at Slackware who are already using xz for their whole repo. According to them you need at least a 486 and 64MB RAM. Does not look like anything we should worry about.
Did some testing with openoffice-base 3.2.0-1-x86_64.tar: compression speed: gzip: 0m28.945s bzip2: 1m21.876s xz -1: 0m49.244s xz -2: 1m18.444s xz -3: 3m34.208s xz -6: 4m41.148s
decompression speed: gzip: 0m 5.772s bzip2: 0m29.433s xz -1: 0m13.983s xz -2: 0m12.949s xz -3: 0m12.706s sz -6: 0m11.462s
Is that right? Decompression gets faster with higher compression ratio?