[gmx-users] Problems with REMD in Gromacs 4.6.3

[gigo]

Dear GMXers,
With Gromacs 4.6.2 I was running REMD with 144 replicas. Replicas were 
separate MPI jobs of course (OpenMPI 1.6.4). Each replica I run on 4 
cores with OpenMP. There is Torque installed on the cluster build of 
12-cores nodes, so I used the following script:

#!/bin/tcsh -f
#PBS -S /bin/tcsh
#PBS -N test
#PBS -l nodes=48:ppn=12
#PBS -l walltime=300:00:00
#PBS -l mem=288Gb
#PBS -r n
cd $PBS_O_WORKDIR
mpiexec -np 144 --loadbalance mdrun_mpi -v -cpt 20 -multi 144 -ntomp 4 
-replex 2000

It was working just great with 4.6.2. It does not work with 4.6.3. The 
new version was compiled with the same options in the same environment. 
Mpiexec spreads the replicas evenly over the cluster. Each replica forks 
4 threads, but only one of them uses any cpu. Logs end at the citations. 
Some empty energy and trajectory files are created, nothing is written 
to them.
Please let me know if you have any immediate suggestion on how to make 
it work (maybe based on some differences between versions), or if I 
should fill the bug report with all the technical details.
Best Regards,

Grzegorz Wieczorek