[libfabric-users] fabtests on Infiniband

[Hefty, Sean]

> fi_msg_pingpong -f verbs -b 10000
> 
> and the client with
> 
> fi_msg_pingpong -f verbs -p 10000 10.0.0.1
> 
> Communication works, however performance is not as expected. Latency
> using ib_send_lat goes up from as low as 0.7 usec, while results from
> fi_msg_pingpong don't get under 4.3 usec (I modified the test_size array

You can't compare the output from these two programs.  They operate differently.  The fi_msg_pingpong test is written more as an example, with a fairly straightforward set of calls.  It waits for completions after each send and for each receive.  The IB perftests is more... interesting, using different send options and completing handling.  Fi_msg_pingpong is closer to ibv_pingpong.  Fi_ubertest is more of a performance benchmark, but even it is structured differently than fi_send_lat.

Note that there's an open PR against fabtests to convert the pingpong examples into benchmarks more closely aligned with the behavior that MPI would use.