[mpich-discuss] version 1.1 strange behavior : all processes become idle for extensive period

[chong tan]

I am seeing this funny situation which I did not see on 1.0.6 and 1.0.8.  Some background:

machine : INTEL 4Xcore 2

running mpiexec -n 4

machine has 32G of mem.  

when my application runs,  almost all memory are used.  However, there is no swapping.
I have exclusive use of the machine, so contention is not an issue.

issue #1 :  processes take extra long to be initialized, compared to 1.0.6
issue #2 : during the run, at time all of them will become idle at the same time, for almost a
                minute.  We never observed this with 1.0.6


The codes are the same, only linked with different versions of MPICH2.

MPICH2 was built with --enable-threads=multiple for 1.1.  without for 1.0.6 or 1.0.8

MPI calls are all in the main application thread.  I used only 4 MPI functions :
init(), Send(), Recv() and Barrier().  



any suggestion ?

thanks
tan


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/mpich-discuss/attachments/20090710/261dae83/attachment.htm>