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On Wed, Aug 31, 2005 at 09:04:21AM -0700, Mark Knecht wrote |
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> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge |
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> mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid |
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> xtpr |
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[...deletia...] |
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> I then looked for CPU flags that had an equivalent USE flag and that |
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> might be of use for faster graphics. On this machine I chose mmx, sse |
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> & sse2. Armed with that I changed my make.conf file to look like this: |
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There are CPU flags and there are USE flags. Some of them have the |
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same names, and that may confuse you. It works like this... |
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1) Get a listing of your cpu's flags in /proc/cpuinfo |
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2) Check against the list of supported flags in gcc for you cpu, and |
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add them to CFLAGS |
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3) Check http://www.gentoo.org/dyn/use-index.xml for a list of valid |
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USE flags, and include any that show up in /proc/cpuinfo |
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4) Repeat step 3) with /usr/portage/profiles/use.local.desc for any |
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programs you're emerging. There doesn't seem to be anything |
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special on your pentium4, but my AMD64 not only has mmx and 3dnow, |
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it also has mmxext and 3dnowext. mplayer can take advantage of |
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them. I include them in the /etc/portage/package.use entry for |
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media-video/mplayer. |
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I'll assume that you're using gcc 3.3.5. In that case, the place to |
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look for CPU flag options is... |
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http://gcc.gnu.org/onlinedocs/gcc-3.3.5/gcc/i386-and-x86_002d64-Options.html#i386-and-x86_002d64-Options |
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That list shows pentium4, mmx, sse, and sse2. Also, if you have *ANY* |
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version of sse available, you can improve performance by running floating |
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point math via sse, rather than 387 instructions. I recommend... |
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CFLAGS="-O2 -pipe -fomit-frame-pointer -march=pentium4 -mmmx -msse -msse2 -mfpmath=sse" |
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http://www.gentoo.org/dyn/use-index.xml shows mmx and sse as valid USE |
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flags, so you can include them in USE. |
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-- |
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Walter Dnes <waltdnes@××××××××.org> |
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My musings on technology and security at http://tech_sec.blog.ca |
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-- |
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gentoo-user@g.o mailing list |
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