CHARMM Development Project Forums User Discussion & Questions Installation and Testing c37a2 charmm with parallelization

I have install the c37a2 charmm with parallelization，and it shows that success,the installation commands is:
./install.com gun xxlarge M

However,when I submit a job, I found the rate is so slow! Even slower than the non-parallelization charmm with just only one CPU!
Besides,I submit the job to the cluster with qsub.and I just use just one node and each node has 8 CPUs.

c37a2 is not a released version.

Please provide more detail about your benchmark: number of atoms, the input file used to run it, the timing data at the end of the output for both the serial and parallel runs (and for the parallel run it is useful to have the output for all nodes)

The results would seem to argue against a successful compilation, but as noted, the lack of detail makes it difficult to judge or offer suggestions. The only case I can think of where this might happen for correctly compiled code is a test system with a fairly small number of atoms.