Why does mpirun return immediately without any output and apparently without running any processes?
There are several things that can cause your job to crash before it even starts. The process launcher by default prevents any popup windows from appearing when your processes crash. So if the job crashes at startup you may not know that it has even run. The two main causes are: 1) You are missing a dll required by the process. Many times you will compile a program that works on the local machine and then crashes on a remote machine because the remote machine does not have the necessary dlls. If you compiled with cygwin you need to make sure the cygwin dll is on all the nodes. If you compile with the Microsoft Visual tools you need to make sure those libraries are available. One way to solve this problem without copying files to the remote nodes is to place all necessary dlls in the same directory as the executable. Windows looks in the directory of the executable first before searching the path for dlls. 2) Your executable is broken. If you place a very large array in the global space
