PETSc.jl and GPUs

[thomasgibson]

In order to use PETSc on GPUs, we'll also need to wrap the necessary data types for CUDA and OpenCL. We'll need to provide the compiled binaries as well; https://www.mcs.anl.gov/petsc/features/gpus.html

[ViralBShah]

@boriskaus I believe we do not build PETSc_jll with GPU support right? Is it something that users expect nowadays? Again, a first step towards getting this eventually is having support in the JLL.

[boriskaus]

No we don't build it with GPU support (I imagine that doing that with BinaryBuilder is a nightmare).

If people are interested in this (which more and more are), they should perhaps build the correct version of PETSc themselves and link that one to PETSc.jl, instead of PETSc_jll. A crucial factor here is that we must ensure that the correct version of PETSc is being linked

[ViralBShah]

We do it increasingly in BinaryBuilder, but it definitely increases complexity. I agree that for now, this is a future feature, and people who need it should use their own PETSc build.

Of course, contributions to do this are welcome (there are several Yggdrasil examples with GPU enabled packages now).