Hello Szilard Many thanks for these very useful comments!
We run jobs on a single node of a small Apple cluster (no Infiniband unfortunately). One node has two Intel(R) Xeon(R) X5650 Processors each with 6 cores and 12 threads, so in total 12 cores and 24 threads. I have compiled GROMACS 4.6.1 with OpenMP and CUDA support (-DGMX_MPI=OFF) Do I understand correctly that this build will work efficiently without gpu but not with gpu as you mention? In order to run gromacs according to your suggestion mpirun -np 2 -ntomp 6 mdrun_mpi -s test.tpr -deffnm test_out -gpu_id 00 Do I need to compile with MPI (i.e. -DGMX_MPI=ON)? Would this then be the most efficient way to run GROMACS in the given hardware set-up (dual socket, total 12 cores and GPU)? Thanks again! Best George > FYI: On your machine running OpenMP across two sockets will probably not be > very efficient. Depending on the input and at how high paralleliation are > you running, you could be better off with running multiple MPI ranks per GPU. This is a bit of an unexplained feature due to it being complicated to > use and not fully supported (does not woth with thread-MPI), but you can essentially make multiple MPI ranks use the same GPU by passing the ID of > the GPU you want to "overload" multiple times (and launching the correct number of MPI ranks). > For instance, in your case you can try putting one MPI rank per socket, both using GPU 0 by: > mpirun -np 2 -ntomp 6 mdrun_mpi -s test.tpr -deffnm test_out -nb gpu -gpu_id 00 > This is briefly explained on the wiki as well: > http://www.gromacs.org/Documentation/Acceleration_and_parallelization#Multiple_MPI_ranks_per_GPU Let us know whether you are able to get useful speedup from GPUs! Cheers, > -- > Szil?rd > On Tue, Mar 12, 2013 at 10:06 AM, George Patargias > <g...@bioacademy.gr>wrote: >> Hi Carsten >> Thanks a lot for this tip. It worked! >> George >> > Hi, >> > On Mar 11, 2013, at 10:50 AM, George Patargias <g...@bioacademy.gr> >> wrote: >> >> Hello >> >> Sorry for posting this again. >> >> I am trying to run GROMACS 4.6 compiled with MPI and GPU acceleration >> >> (CUDA 5.0 lib) using the following SGE batch script. >> >> #!/bin/sh >> >> #$ -V >> >> #$ -S /bin/sh >> >> #$ -N test-gpus >> >> #$ -l h="xgrid-node02" >> >> #$ -pe mpi_fill_up 12 >> >> #$ -cwd >> >> source /opt/NetUsers/pgkeka/gromacs-4.6_gpu_mpi/bin/GMXRC >> >> export >> >> DYLD_LIBRARY_PATH=/Developer/NVIDIA/CUDA-5.0/lib:$DYLD_LIBRARY_PATH mpirun -np 12 mdrun_mpi -s test.tpr -deffnm test_out -nb gpu After detection of the installed GPU card >> >> 1 GPU detected on host xgrid-node02.xgrid: >> >> #0: NVIDIA Quadro 4000, compute cap.: 2.0, ECC: no, stat: >> compatible >> >> GROMACS issues the following error >> >> Incorrect launch configuration: mismatching number of PP MPI >> processes >> >> and >> >> GPUs per node. mdrun_mpi was started with 12 PP MPI processes per >> node, >> >> but only 1 GPU were detected. >> >> It can't be that we need to run GROMACS only on a single core so that >> it >> >> matches the single GPU card. >> > Have you compiled mdrun_mpi with OpenMP threads support? Then, if you do >> > mpirun -np 1 mdrun_mpi ? >> > it should start one MPI process with 12 OpenMP threads, which should >> give >> > you what you want. You can also manually specify the number of OpenMP threads >> > by adding >> > -ntomp 12 >> > Carsten >> >> Do you have any idea what has to be done? >> >> Many thanks. >> >> Dr. George Patargias >> >> Postdoctoral Researcher >> >> Biomedical Research Foundation >> >> Academy of Athens >> >> 4, Soranou Ephessiou >> >> 115 27 >> >> Athens >> >> Greece >> >> Office: +302106597568 >> >> -- >> >> gmx-users mailing list gmx-users@gromacs.org >> >> http://lists.gromacs.org/mailman/listinfo/gmx-users >> >> * Please search the archive at >> >> http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. >> >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists >> > -- >> > Dr. Carsten Kutzner >> > Max Planck Institute for Biophysical Chemistry >> > Theoretical and Computational Biophysics >> > Am Fassberg 11, 37077 Goettingen, Germany >> > Tel. +49-551-2012313, Fax: +49-551-2012302 >> > http://www.mpibpc.mpg.de/grubmueller/kutzner >> > http://www.mpibpc.mpg.de/grubmueller/sppexa >> > -- >> > gmx-users mailing list gmx-users@gromacs.org >> > http://lists.gromacs.org/mailman/listinfo/gmx-users >> > * Please search the archive at >> > http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. >> > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists >> Dr. George Patargias >> Postdoctoral Researcher >> Biomedical Research Foundation >> Academy of Athens >> 4, Soranou Ephessiou >> 115 27 >> Athens >> Greece >> Office: +302106597568 >> -- >> gmx-users mailing list gmx-users@gromacs.org >> http://lists.gromacs.org/mailman/listinfo/gmx-users >> * Please search the archive at >> http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > -- > gmx-users mailing list gmx-users@gromacs.org > http://lists.gromacs.org/mailman/listinfo/gmx-users > * Please search the archive at > http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the > www interface or send it to gmx-users-requ...@gromacs.org. > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists Dr. George Patargias Postdoctoral Researcher Biomedical Research Foundation Academy of Athens 4, Soranou Ephessiou 115 27 Athens Greece Office: +302106597568 -- gmx-users mailing list gmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists