[mvapich-discuss] MPI_THREAD_MULTIPLE support

[Martin Cuma]

Hello,

I am wondering how well is MPI_THREAD_MULTIPLE supported in MVAPICH2 built 
with --with-rdma=gen2. The reason I am asking is that I am getting 
deadlock in my code, which does communication from multiple 
threads/processes. The code is running fine with MPICH2, nemesis device.

The code does bunch of isends/irecvs, the thread number is always the 
same among the communication pair, the processes involved differ. For 
example, if process 0 sends to 1, then all threads (say 0-3) on process 0 
do one send each, addressed to the respective thread on process 1. So, in 
total, I do 4 sends, thr0 proc0 to thr0 proc1, thr1 proc0 to thr1 proc2, 
etc. I am ensuring the right recipient via different tags for each thread.

Can someone please comment their experience with communication pattern 
like that and what could be the cause of the problem I am seeing?

Thanks,
MC

-- 
Martin Cuma
Center for High Performance Computing
University of Utah