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saeed_E

Member

Registered: 2019-12-21

Posts: 237

MP2 frequency with G16 (very very short question)

Dear Tian,
I hope you are doing well, my nice friend.
Based on following system monitor, it seems G 16 is not able to parallelize link 906 of the frequency calculations at the MP2 level and, despite using any desirable CPU numbers (e.g., %nprocshared=8), only one CPU is used. Are you agree with me? Indeed, this is one of the reasons why MP2 frequency takes too much long. Is there any way to force G 16 to perform MP2 frequency calculations using more than only one CPU numbers for some specific links?

Sincerely,
Saeed

Last edited by saeed_E (2023-04-25 16:03:18)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: MP2 frequency with G16 (very very short question)

Dear Saeed,

I don't have a clear answer, you should ask Gaussian staff. Perhaps when %mem is fairly large, the utilization of CPU may somewhat increase.

Best,

Tian

saeed_E

Member

Registered: 2019-12-21

Posts: 237

Re: MP2 frequency with G16 (very very short question)

Dear Tian,

Too many thanks for your highest kindness, my nice friend.
Please be aware that, based on my experience, it seems when the Gaussian staff is asked about a problem, the personal licence is firstly checked by them and if one does not have a valid licence, the question is never answered.

On the other hand, please be aware that I did not employ any value for "%mem" and only used "%nproc=8" but, during link 906, I found that only one CPU is used. Taking your very valuable comment, I would employ a large number of "%mem" together with "%nproc=8" to see if link 906 is executed in a parallel manner.

Once again, thank you very much.

Yours sincerely,
Saeed