GPU memory allocations

[aulwes]

Will malt capture allocations for GPU (e.g., hipMalloc)? If not, would it be straightforward for us to add it?

[svalat]

This is something I really want to do have !

I looked a bit a few months ago (mostly for CUDA, but it is same for AMD GPUs in theory), it should not be too hard in principle.

I would track & count the allocs like the mallocs in some ways.

If we can hook without troubles in the API via LD_PRELOAD to overload the symbols, I would say there is two "hard parts" :

1. Extend a bit MALT to have two memory domains (no blockers "a priori").
2. Need to make some functions to get the memory size for some of the hipMalloc variants, mostly the onces getting some multi-dimensional arrays (hipMalloc3D). Following the spec this might not be a limiter, or there is already somewhere. Or maybe they just call under-hood hipMalloc which might make the capture even simpler.

In the webview the simplest approach is just to expose it in the code annotation and call graph pages. Then more advanced make a dedicated page with charts.

I have a bit of time this month to do things, once 1.5.0 being a bit stable. Maybe I can try to prototype a bit to see if there are blockers.

[svalat]

I made a try on an OpenACC app compiled with nvhpc, it does not looks hard for the MALT internal part, I succeed to get the source annotation done.

I will try to make it clean when having a some time for this.