Thanks Stefano for your guidance. It means our QE is not properly installed. I am a new user of QE and someone has told me about the high value of ecutrho. One more thing, is my input is ok for the slab optimization? Kind regards Habib
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Stefano de Gironcoli Sent: 12 August 2016 12:33 AM To: PWSCF Forum <[email protected]> Subject: Re: [Pw_forum] pw.x parallelisation Dear Habib, There is nothing special in pw.x that happens between 7 and 8 processors. Must be an issue with your machine. On the other hand using an ecutrho < 4 x ecutwfc is wrong and the code should complain about that. stefano (sent from my phone) > On 12 Aug 2016, at 07:18, Ullah, Habib <[email protected]> wrote: > > Dear all > > We have successfully installed Quantum Espresso on our cluster and > calculations with 1 to 7 processors are ok... using example submission > scripts as follows and job script as attached: But when increase the > processor from 7, then the calculations stop without any error, although our > cluster can run a simulation with 120 processors (in case of Metlab). > > #!/bin/bash > #$ -N qe > #$ -q all.q > #$ -cwd > # Send mail at submission and completion of script #$ -m be #$ -M > [email protected] # Parallel Job #$ -pe openmpi_ib 7 . > /etc/profile.d/modules.sh module load shared espresso cd > /home/ISAD/hu203/Test mpirun pw.x -inp 96BiVO4-001.in > > 96BiVO4-001.out > > Searching online found this document: > > http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide.p > df > > pw.x can run in principle on any number of processors. > > Wondering if the following is pertinent to our current problems (or if there > is a problem with our Espresso installation on the cluster): > > Parallelization on PWs: > * yields good to very good scaling, especially if the number of > processors in a pool is a divisor of N3 and Nr3 (the dimensions along > the z-axis of the FFT grids, nr3 and nr3s, which coincide for NCPPs); > * requires heavy communications (suitable for Gigabit ethernet up to > 4, 8 CPUs at most, specialized communication hardware needed for 8 or > more processors ); > * yields almost linear reduction of memory per processor with the number of > processors in the pool. > > We have Mellanox Infiniband cards between servers ... each server has > 192GB RAM and 4x 12 Core 2.4GHz AMD processor > > Kind regards, > Habib > > <BiVO4-001-Big-scf.in.txt> > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
