[Mesa-users] #define LP_MAX_THREADS 8

[Brian Paul]

On 04/24/2013 02:24 PM, burlen wrote:
> Hi,
>
> I've found that llvmpipe driver is capped at max of 8 threads. I'm
> finding that to be a bit on the low side. for example I'm using
> systems with much higher physical core counts, 16 is typical but a few
> specialized smp's I use have as many as 1024 physical cores. Even my
> workstation with 8 physical cores runs one of our opengl codes faster
> up to about LP_NUM_THREADS=20. I had to tweak the define up to 32 for
> testing. Any chance that the max could be increased, or better yet
> could be optionally set to a larger value in the configure script?

I think we could bump it up to 16.  I'll post a patch to the mesa-dev 
list.  If you want to add a configure option, post your patch to the 
mesa-dev list.

I'm curious about what you're rendering.  Approximately how many 
triangles and how large is the image?  What kind of shaders?

Only the rasterization stage is parallelized in llvmpipe, not vertex 
transformation, etc..  Apply Amdahl's law accordingly.

-Brian