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