[Intel-gfx] OpenCL support?

[Jesse Barnes]

On Tue, 21 Sep 2010 14:32:16 +0200
Clemens Eisserer <linuxhippy at gmail.com> wrote:

> Hi,
> 
> > Intel graphics cards are still the only
> > ones that are stable, open source, perform well and support
> > suspend/resume in Linux properly
> Wel, thats kind of a bold statement.

But obviously true, right? :)  (Actually, it's funny, we tend to get
the extremes here; some people say only Intel graphics work well in
Linux, others say our driver stack is unusable.  No one takes the
middle road and admits all stacks have their own set of problems!)

> > I am wondering whether there are any plans to produce an OpenCL
> > library for Intel graphics cards, on Linux or otherwise?
> 
> I don't know about Sandy Bridge and can't speak for future plans, but
> for a GM45 you are better off using an SSE based OpenCL implementation
> executing on your CPU.
> Except some corner cases, Intel-CPUs are usually far more powerful
> than the shaders in the chipsets ;)

With Ironlake and Sandy Bridge the performance of the GPU may make them
more attractive targets if that's what you're looking for.

But there's also power to consider.  For instance, both the GPU and CPU
can decode video, but in may cases offloading to the GPU is much more
power efficient, even if you can't do as many FPS (but then again, you
only want to decode at the video frame rate, not 100fps typically).

IIRC on Ironlake offloading H.264 saves around 12W vs doing it on the
CPU.  Not sure how MPEG2 compares on 965, someone would have to run the
numbers.

-- 
Jesse Barnes, Intel Open Source Technology Center