CPU thread support?

[simonbyrne]

Are we going to support the new CPU multithreading?

cc: @lcw

[vchuravy]

Eventually :)

[jpsamaroo]

@vchuravy you mentioned some issues to me about this during the hackathon. I recall that they were implementing shmem and scratch space. Can you elaborate a bit on these, and any others you can think about, for the benefit of the brave soul who chooses to take this one on?

[lcw]

One place to look is libocca, https://libocca.org, which uses a similar kernel abstraction and has an OpenMP backend.

[vchuravy]

Yes shared memory and scratch memory are both abstractions that currently rely on the GPU hardware to do the right thing. Shared memory is shared across a block and scratch memory is thread local.

I think I have also seen codes in Clima that will require more care so that will take a review.