Parallelization issue
Posted: Tue Dec 27, 2011 5:46 am
I have successfully compiled both with mpif90 (Tried GNU MPICH2, MPICH2 1.4, Intel OpenMPI) and verified that the correct libraries were in the path for each.
When I run VASP compiled this way(just by calling vasp not mpirun) and checked the used resources using top it claims to be using 2000%+ cpu (48 core AMD opteron chipsets). The run completes without error. But as I submit it to multiple processors using mpirun it slows because all threads are looking for the same about of cpu %(which corresponds to multiple cores).
The results are consistent with a working version on another machine.
I considered that it could be a problem with mpirun but I have other software compiled (LAMMPS, GPAW, QE) all of which function correctly.
I am baffled as to why this is happening. Perhaps I am missing an environmental variable?
When I run VASP compiled this way(just by calling vasp not mpirun) and checked the used resources using top it claims to be using 2000%+ cpu (48 core AMD opteron chipsets). The run completes without error. But as I submit it to multiple processors using mpirun it slows because all threads are looking for the same about of cpu %(which corresponds to multiple cores).
The results are consistent with a working version on another machine.
I considered that it could be a problem with mpirun but I have other software compiled (LAMMPS, GPAW, QE) all of which function correctly.
I am baffled as to why this is happening. Perhaps I am missing an environmental variable?