<div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div>Dear all .<br></div><div>I am doing some scalability test with MPI/OpenMP on QE 6.5 compile on IRENE skylake cluster at CEA (France).<br></div><div>I noticed that (as in a past version of QE) I have an apparently  "weird" discrepancy between the WALL time and the CPU time at the end of the calculation. <br><br>(QE 6.5 Intel 2017 + ELPA 2016 )<br>480 mpi processes * N_omp_threads:<br><br></div><div>pw.out_480tasks_1omp:     PWSCF        :  20m54.92s CPU  21m47.65s WALL<br>pw.out_480tasks_2omp:     PWSCF        :  28m 2.16s CPU  16m11.73s WALL<br>pw.out_480tasks_3omp:     PWSCF        :  35m43.95s CPU  14m12.05s WALL<br>pw.out_480tasks_4omp:     PWSCF        :  43m24.46s CPU  13m16.07s WALL<br>pw.out_480tasks_5omp:     PWSCF        :  54m59.95s CPU  13m44.10s WALL<br>pw.out_480tasks_6omp:     PWSCF        :      1h 1m CPU  12m33.37s WALL<br>pw.out_480tasks_7omp:     PWSCF        :      1h12m CPU  13m28.96s WALL<br>pw.out_480tasks_8omp:     PWSCF        :      1h19m CPU  12m41.74s WALL<br></div><div><br></div><div>The WALL TIME seems to be the WALL TIME for 1 omp threads in every run. <br>To that the CPU TIME = WALL TIME * N_omp_threads<br></div><div><br>It this correct according to your experience or not?<br></div><div>Thanks in advance.<br></div><div>Best regards<br></div><div dir="ltr"><br clear="all"><br>-- <br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><span style="background-color:transparent;font-family:Arial;font-size:10pt;font-weight:700;white-space:pre-wrap">Federico IORI</span><br></div><div><span><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:10pt;font-family:Arial;background-color:transparent;font-style:italic;vertical-align:baseline;white-space:pre-wrap">Computational material scientist</span></p><p style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="background-color:transparent;color:rgb(61,133,198);font-family:Arial;font-size:11pt;font-style:italic;font-weight:700;white-space:pre-wrap">Paris Innovation Campus</span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:9pt;font-family:Arial;background-color:transparent;vertical-align:baseline;white-space:pre-wrap"><a href="https://www.google.com/maps/place/Air+Liquide/@48.8297381,2.2016685,11.75z/data=%214m5%213m4%211s0x47e67e61a4fbbdc7:0xca3bea9e80059880%218m2%213d48.7630415%214d2.1333045" style="color:rgb(17,85,204);font-family:arial,sans-serif;font-size:12.8px;white-space:normal" target="_blank">1 chemin de la Porte des Loges</a><br style="font-family:arial,sans-serif;font-size:12.8px;white-space:normal"><span style="font-family:arial,sans-serif;font-size:12.8px;white-space:normal">Les Loges en Josas – 78354 Jouy en Josas cedex</span></span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:9pt;font-family:Arial;background-color:transparent;vertical-align:baseline;white-space:pre-wrap"><span style="font-family:arial,sans-serif;font-size:12.8px;white-space:normal">Tel: +33(0) 6 72 03 66 19 - Mail</span><span style="font-family:arial,sans-serif;font-size:12.8px;white-space:normal">: <a href="mailto:federico.iori@airliquide.com" target="_blank">federico.iori@airliquide.com</a></span><br></span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:9pt;font-family:Arial;background-color:transparent;vertical-align:baseline;white-space:pre-wrap"><img src="https://lh5.googleusercontent.com/jWge08q7BtEKOlxuBF_cj804ywzhJmkjw9rEb5dBZLKyUL_HQkVwhcwNi9vtzVTj-EiY-wQhE18VPSACNFaAFCAWvxp6bEwkTDR6-IjGBqp-Y3Afzx-OxN8OHxXYPLS0Dz9tP8fr" style="border-width: medium; border-style: none; border-color: currentcolor;" width="165" height="40"></span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><br></p></span></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>