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<p>Dear Quantum Espresso Experts,</p>
<p>I am encountering an unexpected message regarding GPU oversubscription when running pw.x with GPU on an HPC system. The system has 4 GPU cores per node. I did not receive any warnings when running calculations with 1 node and 1 GPU (ntasks=1, npools=1) or
with 1 node and 2 GPUs (ntasks=2, npools=2). However, upon running with 1 node and 4 GPUs (ntasks=4, npools=4), I receive the following message: "Message from routine print_cuda_info: High GPU oversubscription detected. Are you sure this is what you want?"</p>
<p></p>
<p>Here's the SLURM batch script I used:<br>
<br>
#!/bin/bash -x<br>
#SBATCH --nodes=1<br>
#SBATCH --ntasks=4<br>
#SBATCH --ntasks-per-node=4<br>
#SBATCH --cpus-per-task=1<br>
#SBATCH --output=TbHf.%j<br>
#SBATCH --error=mpi-err.%j<br>
#SBATCH --gres=gpu:4<br>
<br>
export OMP_NUM_THREADS=1<br>
<br>
srun ~/qe-7.2-gpu/bin/pw.x -nk 4 -nb 1 -nt 1 -nd 1 < inp_pwscf > out_pwscf<br>
<br>
</p>
<p>Based on the <b>environment.f90</b> file, this message is triggered when <i>nproc > ndev * nnode * 2</i>. If I understand correctly, I have nproc (Number of parallel processe)=4, ndev(Number of GPU Devices per Node) =4 and nnode (Number of Nodes)=1. This
condition seems to be false (4 > 8). Despite this, the message still appears. All 4 GPUs were active during the run.</p>
<p>Could you please help me understand why this message is appearing under these conditions? Any insights or suggestions to address this would be greatly appreciated.
<br>
</p>
<p>Thank you in advance for your help!</p>
<p><br>
</p>
<p>PhD student in Forschungszentrum Jülich</p>
<p>Yin-Ying Ting<br>
</p>
<p><br>
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<div class="moz-signature">-- <br>
<p>Forschungszentrum Jülich GmbH<br>
Institute of Energy and Climate Research<br>
Theory and Computation of Energy Materials (IEK-13)<br>
E-mail: <a href="mailto:y.ting@fz-juelich.de" class="moz-txt-link-freetext">y.ting@fz-juelich.de</a>
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