dear all? I have two problems in quantum espresso.
I work a simple structure of graphene.(60 atom) I run my program in cluster with 32 core (4 node) and use? below command for running: export PATH=/opt/espresso/openmpi-1.4.2-install/bin:/opt/intel/composer_xe_2011_sp1.11.339/bin/intel64:$PATH export OMP_NUM_THREADS=1 /opt/espresso/openmpi-1.4.2-install/bin/mpirun -hostfile .nodelist60 -np 32 /opt/espresso/espresso-5.0/bin/pw.x -npool 8 < 60.scf.in > 60.scf.out output file was reported: ?General routines ???? calbec?????? :?? 1832.29s CPU?? 2261.50s WALL (?? 20586 calls) ???? fft????????? :???? 21.02s CPU??? 105.36s WALL (???? 130 calls) ???? ffts???????? :????? 1.83s CPU????? 4.52s WALL (????? 29 calls) ???? fftw???????? :?? 1026.00s CPU?? 2618.48s WALL (?? 33010 calls) ???? interpolate? :????? 6.29s CPU???? 13.35s WALL (????? 29 calls) ???? davcio?????? :????? 0.01s CPU? 23906.83s WALL (????? 88 calls) ? ???? Parallel routines ???? fft_scatter? :??? 295.81s CPU?? 1939.74s WALL (?? 33169 calls) ???? EXX routines ? ????PWSCF??????? :???? 2h 8m CPU?????? 10h48m WALL as you seen , difference between CPU and WALL is very much and? run of program is finished after 12 hours approximately. what can i do for reduce WALL time? another problem is : when i use 32 cores or 16 cores,the speed dose not change considerably. I do not know the parallel of cores is done? badly or must change the parameter for improving run time and performance. can any one help me? thanks for advance. Best Regards somayeh fotoohi -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20120829/4dec2e31/attachment.htm
