Hello Thomas, If I remember correctly, in the grid parallelisation different nodes compute different irreps independently, right?
In that case, and also if I remember correctly, the dvscf file created by each node is incomplete, as it only contains the dvscf computed at that node, it is prettu starightforward to recombine the files; it take a 20-lines fortran program, which I had written some time ago and then lost. Or you can do a tiny modification to the ph code and then attach the files with "cat". However, I'm not sure if you'ld be able to do el-ph calculation afterwards. hth! On Wednesday, 7 September 2016 19:28:38 CEST Thomas Brumme wrote: > Dear all, > > my question is already given in the subject, but I want to > elaborate on it a little bit more. I have big system of 14 atoms > and thus 42 representations. Unfortunately, it is not possible > to use the image parallelization when doing an el-ph coupling > calculation. However, as 42 representations need quite a lot of > time, I run into the time limit of our HPC (just 24h) and always > need to restart calculations for the different q points. > > I would like to know if it is possible to use the GRID parallelization > with el-ph and how to setup it properly. > I now tried a couple of hours and also searched the mail archive > for help, but maybe I used the wrong search terms!? > > Calculating the phonons on a grid is in fact pretty easy and I > have no problems with that. I thought that I could maybe calculate > the phonons on a grid, then (or at the same time?) also calculate > the dvscf and then start the el-ph calculation with trans=.false. > but it is always complaining about something, mostly about > errors while reading the dvscf file... > > Following the 1. grid example I calculated the phonons (I try at > the moment with simple Al) for different q points and > representations. Then - I thought - it would be enough to set > the fildvscf to something once I make the finale calculation to > collect the phonon results. But then I get problems. It seems > the code does not use/recalculate the density. The charge density > files in the iq subfolders of _ph0 were empty. So I copied them > from the grid subdirectories to the iq subfolders into the _ph0 dir. > Now, it seems, that the code is correctly calculating also the > dvscf files. Yet, if I now start the el-ph calculation the code > complains about errors in the dvscf file... > > I could also provide the changed bash script I used to do all > these steps but I think it won't be very helpful. > > If anyone has an idea how to use the grid parallelization for > a phonon calculation with a subsequent el-ph calculation, I > would be very grateful for help. > > Thomas -- Dr. Lorenzo Paulatto IdR @ IMPMC -- CNRS & Université Paris 6 +33 (0)1 44 275 084 / skype: paulatz http://www.impmc.upmc.fr/~paulatto/ 23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05 _______________________________________________ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
