I have a problem with the parallel version of a numerical simulation program for smoke and heat transport from fires, which is called FDS (see www.fds-smv.net). This program is written in Fortran90 (except of one routine in C) and compiled with the Intel 10.1 compiler. FDS can be executed in a serial as well as a parallel way. During the last years I used FDS on a Linux-cluster of up to 18 Intel-Xeon nodes without namable problems. Now, I am concerned with the porting of FDS to a new Windows cluster. The first problem consisted in the fact that I had to use several additional compiler options (/Qftz /fpe3 /Qzero) to get the code to run.
Now, the code can be started on different numbers of processors of the Windows-cluster without any problem, but the runtime behaviour is different from that on the Linux-cluster: The code runs for many hours (normal applications may take one or more weeks!), then it stagnates while still having the indication 'Running' in the job manager of the Windows HPC cluster. Obviously there are some problems with the MPI-communication routines: Several processes seem to wait for others (staying employed), resp. they iterate much faster than other ones although each iteration uses a MPI_BARRIER-command for synchronization!!
This problem doesn't occur at all on the Linux-Cluster where the same code with Intel compilation runs for weeks without any changing of the code!!! After searching and debugging for many days I haven't any idea what to do next and would be very grateful if somebody could give me an advice how this problem can be solved. Is this a known problem and has somebody else similar problems, respectively?
Many thanks in advance,