[mvapich-discuss] Bandwidth on single hca dual port multirail configuration

[Jie Cai]

We have single ConnectX dual port HCA cluster installed, and try to
build a dual port multirail IB cluster.

I have tested to run OSU put bandwidth test on the cluster with MVAPICH2.

mpirun_rsh -ssh -np 2 node02 node01 MV2_NUM_HCAS=1 MV2_NUM_PORTS=2
MV2_NUM_QP_PER_PORT=1 ./osu_bandwidth

However, I didn't achieve bandwidth improvement. The peak bandwidth I
got for the test is 1458.93 MB/s, which is far from the expectation
(2.5GB/s).

Does anyone knows what's going on?

-- 
Jie Cai