[QE-users] [QE-GPU] High GPU oversubscription detected

[Paolo Giannozzi]

On 11/30/23 10:24, Yin-Ying Ting wrote:

> Could you please provide guidance on resolving the oversubscription 
> issue? 

if your job runs on 4 GPUs while pretending to run on one, there is no 
real issue: just ignore the message. If you instruct your job to run on 
4 GPUs but it doesn't, you should report it to your system administrator.

Paolo




> 
> Kind regards,
> 
> Yin-Ying Ting
> 
> 
> On 29.11.23 15:53, Paolo Giannozzi wrote:
>> On 11/27/23 11:32, Yin-Ying Ting wrote:
>>
>>> Based on the *environment.f90* file, this message is triggered when 
>>> /nproc > ndev * nnode * 2/. 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.
>>
>> funny. Even funnier, the number of GPUs actually used does not seem to 
>> be written anywhere on output.
>>
>> Add a line printing nproc, ndev, nnode just before the warning is 
>> issued, recompile and re-run. One (at least) of those numbers is not 
>> what you expect. Computers are not among the most reliable machines, 
>> but they should be able to find out who is larger between 4 and 8
>>
>> Paolo
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> Forschungszentrum Jülich GmbH
> Institute of Energy and Climate Research
> Theory and Computation of Energy Materials (IEK-13)
> E-mail: y.ting at fz-juelich.de
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-- 
Paolo Giannozzi, DMIF, Univ. Udine, Italy
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