Problem with CCSD-T energy calculation

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Stephan P. A. Sauer

Aug 22, 2021, 2:58:27 PMAug 22
to dirac-users
Dear all,

I am trying to run a CCSD-T calculation, which is maybe a bit big and
the jobs just keeps doing on me and I cannot figure out why (not
enough memory or disk full or whatever), because I don't get a real
error message.

Maybe there is not enough memory, because I am not sure, whether I
really understand the use of the -ag and -gb options to pam.

I attach the output file and the error file from the queue system. Any
suggestion will be very welcome.

Best wishes

Ilias Miroslav, doc. RNDr., PhD.

Aug 22, 2021, 3:58:13 PMAug 22
to dirac-users

the demand is :
Predicted RelCC memory demand: 77.686 GB

but "
DIRAC master (node218.cluster) starts by allocating 4026000000 r*8 words ( 29.996 GB) of memory"  ... you assign only 30GB via --gb

please use --ag=80   --gb=79 per 1 MPI thread

for example, on machine with 256GB RAM  you can afford --mpi=3, that is 3 MPI threads


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Subject: [dirac-users] Problem with CCSD-T energy calculation
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Stephan P. A. Sauer

Aug 23, 2021, 4:42:36 AMAug 23
Dear Ilias,

thanks a lot for this suggestion. I will try it immediately.

Mvh / Best wishes / Mit freundlichen Grüssen

Stephan P. A. Sauer
Head of Section Physical Chemistry

Department of Chemistry, University of Copenhagen
Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
Tel : +45-35320268
E-mail : (research related issues) (administration related issues)

Author of Molecular Electromagnetism: A Computational Chemistry Approach
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