Re: threading in mesa

On 12/07/2012 08:19 PM, burlen wrote:
> Hi Brian,
>
>> Be aware that the llvmpipe driver does not work with the OSMesa
>> interface.
> :-(
>
> that's no fun. In general, I would really like to be using llvmpipe
> driver. If I'm reading mesa docs correctly it's the only one that
> supports threading and provides glsl.

GLSL 1.30 should work with OSMesa, but yeah, no threading there.


> I'm using osmesa without x on
> systems like cray xe, 24 cores per node, and sgi uv 1000 1024 cores.
> Soon we'll also be using an intel mic cluster, each card will have 60
> cores with 2 hardware threads, and 2 hyper threads. I would expect
> that the threaded driver would make a big difference on these systems.
>
> Is there any info on the performance or scaling of the threaded
> llvmpipe driver?

I don't know if anyone's tried LLVMpipe with more than 8 cores (that's 
all I have).  And I haven't done any comparisions of perf as a 
function of number of cores lately.  The perf probably flattens out at 
some point.  That would be a good project for someone.

There seem to be quite a few people interested in OSMesa+LLVMpipe but 
I just haven't had the time to implement it.

-Brian