epw.x runs on AMD Zen4 cpus is much slow than inteL cpus

Post here questions linked with issue while running the EPW code

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zcy
Posts: 1
Joined: Sun Jan 05, 2025 1:18 pm
Affiliation: Doctor

epw.x runs on AMD Zen4 cpus is much slow than inteL cpus

Post by zcy »

Dears Professors and develops.
When practice sic example, it is found that epw.x runs on AMD Zen4 cpus is much slower than inteL cpus when calculating self-energy. epw.x on both was compiled with intel icc and ifort with mkl.

Do you have any solution?
stiwari
Posts: 51
Joined: Mon Jun 26, 2023 9:48 pm
Affiliation: UT Austin

Re: epw.x runs on AMD Zen4 cpus is much slow than inteL cpus

Post by stiwari »

Hi

Can you kindly post the system size (k-grid, q-grid, and number of bands (nbndsub)) along with parallelization setting used for running epw.x? Also, can you post the output files?

The possible reason for such drop in performance can be the compilation of epw. It may be useful to try compiling epw using gcc compiler. Also, if you find a large difference between wall time and cpu time, try using etf_mem = 1 for such case.

Best regards,
Sabya.
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