CCL: Command to run QE-GPU

From: "Anson Thomas" <a_thomas]*[cy.iitr.ac.in>
Subject: CCL: Command to run QE-GPU
Date: Thu, 30 Sep 2021 22:08:14 -0400

 Sent to CCL by: "Anson   Thomas" [a_thomas**cy.iitr.ac.in]
 Hello.
 I have installed quantum espresso with GPU support on a system.
 Ubuntu 18.04.5 LTS (GNU/Linux 4.15.0-135-generic x86_64)
  System Configuration:
  Processor: Intel Xeon Gold 5120 CPU 2.20 GHz (2 Processor)
  RAM: 96 GB
  HDD: 6 TB
  Graphics Card: NVIDIA Quadro P5000 (16 GB)
  Usually, without GPU support, I submit jobs simply using: mpirun pw.x -inp
 input.in > output.out. The output file in such cases includes these lines:
  Parallel version (MPI), running on    28 processors
      MPI processes distributed on     1 nodes
      K-points division:     npool     =       2
      R & G space division:  proc/nbgrp/npool/nimage =      14
      wavefunctions fft division:  Y-proc x Z-proc =       2      7
      wavefunctions fft division:  task group distribution
                                   #TG    x Z-proc =       2      7
  However, I do not understand what additional parameters are to be included
 while running with GPU support to use it. I read about -ndiag, ntg, npool and
 other options on the internet but could not understand how to use them for my
 configuration.
 I would be really grateful if someone could give more insight into using
 these options to use GPU in my calculations fully.
  Thanks in advance.