vasp running out of memory

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Hi,

I have a user at SDSC (www.sdsc.edu) who is trying to run a vasp 5.4.4 job on one of our clusters and it seems to want to grab an infinite amount of memory. I ran his job on one of our large memory nodes (> 2TB) with a small number of processors and it still failed ( I monitored the memory use as it ran)

The attached tar file contains the input files, OUTCAR and the standard output file

Thanks,

Jerry

[pedro_melo]

Dear Jerry,

Unfortunately your system is too large, so I will not be able to run it myself and reproduce the issue. However, could you start by using the vasp_std executable, instead of vasp_ncl? Your system does not have spin-orbit coupling, so I do not see a need to use the non-collinear version. This should already reduce the amount of memory needed.

Could you also try setting LSPECTRAL=.FALSE.? This should reduce the amount of memory needed.

Finally, if you have access to VASP 6.x you can use the low-scaling GW method described here.

Let me know if this helps with your case. Kind regards,
Pedro

[alex]

Hi Jerry,

another point to consider is also the number of k-points along c/z, which is 5 in your users case. I see the point that for that kind of calculations you don't want to waste precision somewhere else, but c-axis is already ~7 A long, so your user might also go away with a cheaper set (which could be tested with DFT or at least cheaper than GW simulations).

Hth,

alex

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Thanks very much! The user is not licensed for vasp 6 but he will try the other suggestions.

The user has a question about MAXMEM: he wants to know if that is working since there is no mention of it OUTCAR: (I did point out to him that it is in the xml file)

Jerry

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The user just wanted to verify that MAXMEM is actually being used.

Thanks,

Jerry

[pedro_melo]

Dear Jerry,

As written here, MAXMEM is indeed read during GW calculations, which is what your user is running.

Kind regards,
Pedro