[petsc-dev] PETSc programming model for multi-core systems

[Barry Smith]

On Nov 11, 2010, at 6:15 PM, Matthew Knepley wrote:

> On Fri, Nov 12, 2010 at 9:52 AM, Barry Smith <bsmith at mcs.anl.gov> wrote:
> 
>   What should we use a for programming model for PETSc on multi-core systems? Currently for conventional multicore we have only have one MPI process per core and for GPU we have subclasses of Vec and Mat with custom CUDA code.
> 
>   Should we introduce subclasses of Vec and Mat built on pthreads (this is what Bill G recommends, and not to use OpenMP)?
> 
> pthreads are a nightmare and do not do vectorization right, which is necessary here.

   What do you mean do not vectorize?

> I am for OpenCL/CUDA. Eventually
> I think OpenCL will take its head out of its ass and be as nice as CUDA.

   That's fine for GPUs but what about 8 core or 12 core Intel processors? CUDA for that also?

   Barry

> 
>   Matt
>  
>   Is there a way to have some kind of consistent model between conventional multicore and GPU multi-core? If not the same code. What about this MCUDA stuff?
> 
>   Barry
> -- 
> What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
> -- Norbert Wiener