Re: [gentoo-user] USE="mmx mmxext sse sse2 ssse3 3dnow 3dnowext"

[Daniel Iliev <daniel.iliev@gmail.com>]

On Tue, 26 May 2009 06:00:10 +0100
Stroller <stroller@stellar.eclipse.co.uk> wrote:


> Looks like `echo media-video/mplayer mmx mmxext sse sse2 ssse3 3dnow  
> 3dnowext >> /etc/portage/package.use` unless someone else is able to  
> be more informative.
> 
> Stroller.
>   


Yes, just add "cpudetection" to those or put it in in make.conf.

If you want to set the proper flags there's no other way but
to check what features the particular CPU model supports. The only sure
thing is that no Intel CPUs support AMD's 3now and 3dnowext.
Everything else depends on the moment the particular model was
released, because those features were not initially specified but
being added as time passes by.

Some random thoughts...

The packages that could utilize some of those cpu instruction sets are
not so many. Try "euse -i sse" for example and see which programs would
be affected if you change it. Then...trial and error. :)

Last but not least. If you have a (supported model of) NVidia
video card and don't mind using the closed source driver, you could try
VDPAU. It's a technology for Linux for offloading video decoding from
CPU to GPU. For a reference mplayer takes about 30% on my CPU to play
HD clips normally and about 2% when using VDPAU.

HTH

-- 
Best regards,
Daniel