Kernel Optimizations Regarding SSE
Anthony M. Agelastos
iqgrande at gmail.com
Sun May 29 07:48:23 PDT 2005
Hello all,
I am, as we converse, rebuilding world to 5-STABLE (from 5.4-STABLE 3
weeks ago). This is the first time that I am building a custom kernel
and it only deviates from GENERIC in that I only have
cpu I686_CPU (without the I586 and I486 that were there from
GENERIC)
and I added
option CPU_ENABLE_SSE (per the Handbook's suggestion for Video
Playback)
That is it. In watching the compile of the new kernel, I notice that
just about every cc command has the options:
-mno-mmx -mno-3dnow -mno-sse -mno-sse2
Is it me, or does those flags appear to be turning off the very thing
I wanted turned on (to turn it on, wouldn't it be -mmmx -m3dnow -msse
-msse2)? My machine, since it is busy right now compiling in Single
User Mode and I can't get to dmesg, is running 5.4-STABLE synced from
3 weeks ago, compiling 5-STABLE synced from yesterday evening (EDT).
My machine's specs are as follows:
Pentium III // 450 MHz
320 MB RAM
Nvidia Riva TNT / 8 MB VRAM
Back when I had Gentoo on this machine, I had to enable sse and sse2
when I compiled things like MPlayer so the machine could handle
playing back DVDs (and not drop half of the frames). After reading
through make.conf's example and its manpage, I was also wondering if
these (sse) were options that I should put in there (and if so, how
do I do it)? Any and all guidance on the matter would be greatly
appreciated. Thank you.
-Anthony
PS - In case it is relevant, and I am forced to go off of memory
since my machine is still compiling, my make.conf file has the flags
required so that when things compile, they have the options
-O -pipe -march=pentium3
(there are only about 3 lines in there... I can list them if needed
once this is done compiling).
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