<div dir="ltr"><div>Your supercell is small but you have a high cutoff and a large number of k-points, which makes the overall computational load quite heavy. Moreover your choice of parallelization is less than optimal: you should use both k-point and plane-wave parallelization, something like "mpirun -np 160 pw.x -nk 16" or so. For reference: I ran your <a href="http://Fe.pw.scf.in" target="_blank">Fe.pw.scf.in</a> input in 20' on a small 36-core machine with two (powerful) GPU's. The nscf calculation took 1h20' for the calculation and is taking as much time if not more to write the files. Also note that not all postprocessing calculations are optimized for large runs.</div><div><br></div><div>Paolo<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Mar 15, 2021 at 7:23 PM Lenz Fiedler <<a href="mailto:fiedler.lenz@gmail.com" target="_blank">fiedler.lenz@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">(resent because something went wrong with the header line)<br><div><br>Hi users,<br><br>I am experiencing a problem with pp.x. I want to calculate the LDOS for a 16 Fe atom supercell using a 560 value energy grid and the 3D grid given by the DFT calculation (100x100x100 grid points). I have performed the DFT calculation by first doing a SCF calculation (8x8x8 k-points) and then a non-SCF calculation (14x14x14 k-points) successfully. Now I am trying to do: <br><br>mpirun -np 160 pp.x -in <a href="http://Fe.pp.ldos.in" target="_blank">Fe.pp.ldos.in</a><br><br>but the calculation takes way longer than I anticipated. The entire DFT calculation took less than a day, while for the LDOS, after about 12 hours, only 20 tmp files had been written. Am I doing something wrong? Or is this expected? At this rate, calculating the LDOS would take days, which is why I am assuming I am doing something wrong. <br>Please find my output and input files here:<br><br><a href="https://drive.google.com/drive/folders/1R-m5jlw1bcNxe3nBXjc4dms-IoMMp4Ir?usp=sharing" target="_blank">https://drive.google.com/drive/folders/1R-m5jlw1bcNxe3nBXjc4dms-IoMMp4Ir?usp=sharing</a><br>(the pp.out file is from a run where I investigated if a lower number of CPUs helps, but that was slower, as expected.)<br><br>Kind regards<br>Lenz<br><br>PhD Student (HZDR / CASUS)</div></div>
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