Re: [QE-users] Huge difference between Wall time and CPU time in electron-phonon calculation

2020-10-07 Thread Paolo Giannozzi
If your cluster has a disk per node with a local (i.e., directly accessible by the node but not visible from other nodes) you may try to write data to that disk. It's a pain in the *** and may require some tweaking, but it might work. You need to ensure that the directories are there (they are cre

Re: [QE-users] Huge difference between Wall time and CPU time in electron-phonon calculation

2020-10-07 Thread pippo pippo
Dear Lorenzo and Michel, thank you for your reply. Yes, unfortunately I am using a small cluster and, for memory issues, I cannot use the SSD-based local scratch. Thus I am forced to use a non-parallel NFS. From your answers, I understand that, given the situation, the huge difference between t

Re: [QE-users] Huge difference between Wall time and CPU time in electron-phonon calculation

2020-09-30 Thread Michal Krompiec
Dear Rafaello, Are you using a local (preferably SSD-based) scratch drive, or a very fast parallel file system? Best wishes, Michal Krompiec Merck KGaA On Wed, 30 Sep 2020 at 15:05, Raffaello Bianco < raffaello.bianco...@gmail.com> wrote: > Dear QE users and developers, > > I am doing an electro

Re: [QE-users] Huge difference between Wall time and CPU time in electron-phonon calculation

2020-09-30 Thread Lorenzo Paulatto
Hello Raffaello, the first thing you should do, is be sure that your are writing to some high performance filesystem. This is often called scratch in computing centers, to be sure you should ask the people responsible. cheers On 9/30/20 4:04 PM, Raffaello Bianco wrote: Dear QE users and deve

[QE-users] Huge difference between Wall time and CPU time in electron-phonon calculation

2020-09-30 Thread Raffaello Bianco
Dear QE users and developers, I am doing an electron-phonon coupling calculation in this way (I am using QE v 6.6). First, I have done an scf calculation. Then, I have done a phonon calculation where I have printed the dvscf files, with fildvscf = 'dvscf' Subsequently, I have done th