| 1 |
Hi! |
| 2 |
|
| 3 |
Some binary distros like Mandrake and suse patches their glibcs with |
| 4 |
x86_64 optimized strings and an x86_64 optimized libm to improve |
| 5 |
performance. |
| 6 |
|
| 7 |
I tried extracting those patches from an mandrake SRPM and add them to |
| 8 |
the glibc 2.3.5 ebuild. The x86_64 optimized strings patch built and |
| 9 |
worked perfectly and gave a large speedup as you can see below. But I |
| 10 |
couldn't get glibc to build with the libm patch because of unresolved |
| 11 |
symbols (and I'm no programmer so I have no idea how to fix that). |
| 12 |
|
| 13 |
I found a small C program on a suse mailing-list to measure glibc memory |
| 14 |
copy performance: |
| 15 |
http://lists.suse.com/archive/suse-amd64/2005-Mar/0220.html |
| 16 |
|
| 17 |
With the glibc 2.3.5 currently in gentoo I get: |
| 18 |
isidor ~ # ./memcpy 2200 1000 1048576 |
| 19 |
Memory to memory copy rate = 1291.600098 MBytes / sec. Block size = 1048576. |
| 20 |
|
| 21 |
But with glibc 2.3.5 + amd64 optimized strings I get: |
| 22 |
isidor ~ # ./memcpy 2200 1000 1048576 |
| 23 |
Memory to memory copy rate = 2389.321777 MBytes / sec. Block size = 1048576. |
| 24 |
|
| 25 |
That's an improvement of over 1000mb/s! Suse 9.3 also gives about |
| 26 |
2300mb/s out of the box. |
| 27 |
|
| 28 |
How about adding these patches to gentoo? Perhaps in glibc 2.3.5-r1 |
| 29 |
before it leaves package.mask? I'll create a bugreport about it if you |
| 30 |
agree! |
| 31 |
|
| 32 |
This .tar.bz2 contains the glibc directory from my overlay with the |
| 33 |
mandrake patches included in files/mdk, but the libm patches are |
| 34 |
commented out in the ebuild. |
| 35 |
http://snigel.no-ip.com/~nxsty/linux/glibc.tar.bz2 |
| 36 |
|
| 37 |
-- |
| 38 |
Simon Strandman <simon.strandman@×××××.com> |
| 39 |
|
| 40 |
-- |
| 41 |
gentoo-amd64@g.o mailing list |
Archives