Hi all,

 I have a distributed program running on 400+ nodes and using OpenMPI. I have run the same binary with nearly the same setup successfully previously. However in my last two runs the program seems to be getting stuck after a while before it completes. The stack trace at the time it gets stuck is as follows:

 #0  0x00002ad0000c00df in poll () from /lib/libc.so.6
#1  0x00002acfffa49c27 in opal_poll_dispatch () from /usr/lib64/libopen-pal.so.0
#2  0x00002acfffa47add in opal_event_base_loop () from /usr/lib64/libopen-pal.so.0
#3  0x00002acfffa43203 in opal_progress () from /usr/lib64/libopen-pal.so.0
#4  0x00002acfff78b315 in ompi_request_test_some () from /usr/lib64/libmpi.so.0
#5  0x00002acfff7adf7a in PMPI_Testsome () from /usr/lib64/libmpi.so.0

I checked all the nodes and they seem to be up and doing fine. Any suggestions/hints on what might be happening here would help greatly. Thanks in advance.

I am using OpenMPI 1.2.7 on gentoo linux.