glibc recompile - optimized for G5 cpu target
Hi,
Ok, i have modified the debian rules file for glibc 2.21-6 and recompiled.
I have built this package essentially with the cflags: -O3 together with
the following extra line below:
extra_cflags = -mcpu=G5 -mtune=G5 -maltivec -mabi=altivec
Ill be the first to admit that i haven't played around with glibc before.
Not sure if this will even make any difference, just wanted to try an
experiment for myself.
It compiles, runs through the tests and builds the packages.
The build logs are approximately 13MB each for powerpc and powerpc64!
The following log files in the build-tree
test-results-powerpc64-linux-gnu-ppc64 &
test-results-powerpc-linux-gnu-libc both came up with no logged
testsuite failures. I assume these logs are where to look for obvious
testsuite regressions?
After compilation, I have the following deb packages:
glibc-doc_2.21-6+local-g5.1_all.deb
glibc-source_2.21-6+local-g5.1_all.deb
libc6_2.21-6+local-g5.1_powerpc.deb
libc6-dbg_2.21-6+local-g5.1_powerpc.deb
libc6-dev_2.21-6+local-g5.1_powerpc.deb
libc6-dev-ppc64_2.21-6+local-g5.1_powerpc.deb
libc6-pic_2.21-6+local-g5.1_powerpc.deb
libc6-ppc64_2.21-6+local-g5.1_powerpc.deb
libc6-ppc64-dbgsym_2.21-6+local-g5.1_powerpc.deb
libc6-udeb_2.21-6+local-g5.1_powerpc.udeb
libc-bin_2.21-6+local-g5.1_powerpc.deb
libc-bin-dbgsym_2.21-6+local-g5.1_powerpc.deb
libc-dev-bin_2.21-6+local-g5.1_powerpc.deb
libc-dev-bin-dbgsym_2.21-6+local-g5.1_powerpc.deb
libc-l10n_2.21-6+local-g5.1_all.deb
libnss-dns-udeb_2.21-6+local-g5.1_powerpc.udeb
libnss-files-udeb_2.21-6+local-g5.1_powerpc.udeb
locales_2.21-6+local-g5.1_all.deb
locales-all_2.21-6+local-g5.1_powerpc.deb
multiarch-support_2.21-6+local-g5.1_powerpc.deb
nscd_2.21-6+local-g5.1_powerpc.deb
nscd-dbgsym_2.21-6+local-g5.1_powerpc.deb
I have installed the recompiled glibc on a spare hdd with an older
install of Debian and the installation still seems to have survived
(actually surprised me more than anything else)!
I'm not expecting miracles (or anything positive TBH) but would lmbench
be an appropriate benchmark to run to compare the performance of glibc
(i.e. original Debian 2.21-6 vs 2.21-6 with G5 cflags) or any other
benchmark recommendations?
I know, i know.... This is unsupported!
Regards,
Peter
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