Dear All, Could anyone tell me the important tuning
parameters in openmpi with IB interconnect? I tried setting eager_rdma,
min_rdma_size, mpi_leave_pinned parameters from the mpirun command line on 38
nodes cluster (38*2 processors) but in vain. I found simple mpirun with no mca
parameters performing better. I conducted test on P2P send/receive with data
size of 8MB. Similarly i patched HPL linpack code with
libnbc(non blocking collectives) and found no performance benefits. I went
through its patch and found that, its probably not overlapping computation with
communication.Any help in this direction would be appreciated.-Neeraj
