Hey guys! Yesterday I found this article http://gentoo-wiki.com/HOWTO_Speed_up_decompression_with_pbzip2 and was very happy, because I'm an owner of an Q6600.
So I tried to reproduce the benchmark from the wiki article but got that bad results: test # time *bzip2* -d -kf linux-2.6.23.tar.bz2 real 0m11.672s user 0m11.306s sys 0m0.367s test # time *pbzip2* -d -p4 -kf linux-2.6.23.tar.bz2 real 0m25.554s user 0m24.862s sys 0m0.683s So the parallel version took more than the double time! To test whether this is a problem of my Pc I tested this on an Dual Core with the same result. An test with 7z was much better: test # time *7za* x -y linux-2.6.23.tar.bz2 real 0m4.642s user 0m8.379s sys 0m0.327s All tests where done in a tmpfs off 1GB on 2GB RAM. So my questions is what did I do wrong? I also tested it with different CFLAGS, but my CFLAGS are basically very conservative. (-O2 -march=prescott -pipe -fomit-frame-pointer)
