[libfabric-users] Tagged message question

[Hefty, Sean]

> I guess that for complex messages with lots of large and small data items I am better
> off with my hand-rolled protocol - but it would be lovely if I could somehow reuse the
> libfabric internal protocols for each array. (I guess I could send an unexpected
> message with info, generate tags for each large array and get the receiving end to post
> the required tagged buffers - I'll ponder this).

It sounds like this might work.

> Also - I use 64bit tags that are semi random (derived from pointer addresses) - does
> having very large 64bit tag values impact performance in any way? Should I try to use
> simple integer indexes? I don't know if you have some kind of map lookup to match tags
> to buffers or if there is another mechanism.

Tag matching ends up being a list walk.  So the tag values don't matter.