libfabric-2.0: separate FI_DIRECTED_RECV capability for message and tagged message

Question

libfabric-2.0: separate FI_DIRECTED_RECV capability for message and tagged message

j-xiong opened this issue 2 months ago · comments

Jianxin Xiong commented 2 months ago

Define new bits that only applies to message or tagged message. The original cap covers both.

Jianxin Xiong · Answer 1 · Wed Apr 03 2024 00:20:47 GMT+0800 (China Standard Time)

The purpose is to allow transport to support only one of them due to hardware limitation.

Ken Raffenetti · Answer 2 · Wed Apr 03 2024 03:57:52 GMT+0800 (China Standard Time)

MPICH only utilizes this capability for tagged messages, so splitting it should be no issue for us.

Steve Welch · Answer 3 · Thu Apr 04 2024 23:24:57 GMT+0800 (China Standard Time)

It also allows enables full non-matching interface performance with FI_MSG (no initiator matching) while maintaining full matching for FI_TAGGED (tag and initiator) even if hardware supports it for both. Seems particularly useful in the above use case where FI_DIRECTED_RECV is only used on FI_TAGGED.