Discussion Round: Pain Points

[crtrott]

[stvdwtt]

Clarify blocking status in the documentation:
I've been uncertain which Kokkos calls block and which don't, so I add many fences to be safe (e.g. after all deep_copies) under the assumption that they don't block. It makes sense that some fence internally and some don't, I think the best solution is to be clear in the documentation. (Ignore this if that's already been addressed, I haven't checked in a bit.)

Some deep_copy restrictions unexpected:
I don't recall the exact setup, but I've had cases where what cannot be done with deep_copy is not obvious from the description in the documentation. Mostly this has related to deep copying a subview into a compact view with a different layout. I had a conversation on Slack that clarified that deep_copy was acting as it should, so I don't think it is a bug or correctness issue, just a place where perhaps the documentation could be clearer. (Admittedly, this kind of a deep_copy is pretty niche.)

[dalg24]

Notes

• Reduction over a subset of dimensions: Not an MDRange, extremely difficult to offer something performant
• Typelist with all the available execution space, useful to instanciate something on all backends
• Global device symbol: not possible on all backends, really messy on backends where it works
• clarify blocking status: good, should be done
• deep_copy restrictions undocumented: improving the doc is always a good idea