Dear Marcos I have performed a 77-atom B3LYP calculation using VASP on 36 cores. It crushed and showed segmentation fault. Then I tried on a machine with larger memory, it worked, but spent 3 days finishing a loop, so I quit. In my opinion, the hybrid function calculation is quite time consuming and memory demanding in plane wave basis. It is better to do such calculation on a localized basis code such as Gaussian. On Sun, 18 May 2014 11:10:59 -0300, Marcos Ver?ssimo Alves <marcos.verissimo.alves at gmail.com> wrote: > Hi all, > > This is a bit off-topic, but I'm sure there will be many knowledgeable > people around. It's related to the parallel compilation of QE. > > I'm trying to run HSE calculations for a 71-atom silicene sheet, using > Espresso compiled with ifort (composerxe), mpich2 and intel mkl included in > this version of the compiler. Mpich 2 is compiled using gcc/ifort. > > All goes well in the scf part until it gets to the hybrid functional > calculation. Then it crashes with an mpi error (Bad termination, code > 9) which the mpi faq says is usually due to the fact that there is a > segmentation fault in the code, not in mpi. They also state that this is > usually a segmentation fault. > > I wonder if anyone has run HSE calculations for systems as large as this, > and if they have run into this problem. > > One possibility that came to my mind is that, if this is a segmentation > fault, maybe 4-byte integers are not large enough to address all the > indexes of the arrays allocated in the hybrid functional part of the > calculation. I tried to compile QE with 8-byte integers but I get an mpi > error, which I suppose is due to integers being compiled with 4-byte > integers on the C side of the compilation. > > So, I have two questions: > > 1) Is there any way of compiling Mpich 2 with 8-byte integers using gcc? > > 2) If the parallel part were carried out with OpenMP instead of Mpich (I > have 32 cores in the same node of the computer I'm running the > calculation), perhaps this could be a workaround for this problem. Is it > possible to compile QE in parallel mode using only OpenMP and MKL? If yes, > what options would need to be set for either configure or make.sys > directly? Configure already detects the mpi environment, and sets make.sys > to compile QE using it. > > Any help would be greatly appreciated, and I would gladly supply the input > file along with the pseudo I am using (from the QE database) if the > developers would like to run tests on it. > > Best regards, > > Marcos
-- Department of Physics, South University of Science and Technology of China
