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Hi! |
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|
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Some binary distros like Mandrake and suse patches their glibcs with |
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x86_64 optimized strings and an x86_64 optimized libm to improve |
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performance. |
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|
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I tried extracting those patches from an mandrake SRPM and add them to |
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the glibc 2.3.5 ebuild. The x86_64 optimized strings patch built and |
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worked perfectly and gave a large speedup as you can see below. But I |
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couldn't get glibc to build with the libm patch because of unresolved |
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symbols (and I'm no programmer so I have no idea how to fix that). |
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|
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I found a small C program on a suse mailing-list to measure glibc memory |
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copy performance: |
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http://lists.suse.com/archive/suse-amd64/2005-Mar/0220.html |
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|
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With the glibc 2.3.5 currently in gentoo I get: |
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isidor ~ # ./memcpy 2200 1000 1048576 |
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Memory to memory copy rate = 1291.600098 MBytes / sec. Block size = 1048576. |
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|
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But with glibc 2.3.5 + amd64 optimized strings I get: |
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isidor ~ # ./memcpy 2200 1000 1048576 |
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Memory to memory copy rate = 2389.321777 MBytes / sec. Block size = 1048576. |
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|
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That's an improvement of over 1000mb/s! Suse 9.3 also gives about |
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2300mb/s out of the box. |
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|
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How about adding these patches to gentoo? Perhaps in glibc 2.3.5-r1 |
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before it leaves package.mask? I'll create a bugreport about it if you |
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agree! |
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|
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This .tar.bz2 contains the glibc directory from my overlay with the |
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mandrake patches included in files/mdk, but the libm patches are |
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commented out in the ebuild. |
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http://snigel.no-ip.com/~nxsty/linux/glibc.tar.bz2 |
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|
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-- |
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Simon Strandman <simon.strandman@×××××.com> |
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|
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-- |
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gentoo-amd64@g.o mailing list |