A new simulation computer for Code_Saturne

[Gareth_HHU]

Hello!

I am a beginner on Linux and Code_Saturne. I have a problem about computer configuration.
I want to buy a computer for further work. What are the main configuration requirements for Code_Saturne? Is AMD EPYC a good choice for CPU?
I mainly use Code_Saturne and Telemac (also developed by EDF).

All regrads

Gareth

[Yvan Fournier]

Hello,

It is difficult to recommend a specific processor type, because we only have limited benchmark data, and performance can vary strongly between variants of a given architecture, depending on bandwidth, cache, ...

The code is more memory bound than compute bound, so having many cores is not so useful if the memory bandwith does not follow. Initial tests on one machine with EPYC processors seem to show limited performance because of that, but I have not yet looked at those in detail.

As for memory usage, consider you will need about 1.5 Gb per million cells is a mesh. Performance is best when remaining under 50 to 80 thousand cells per core. Here again, I have seen the same build of code_saturne can saturate the memory bandwidth using 2 to 3 cores on some processors (desktop Intel Xeons), while scaling OK using 5 to 7 cores on other machines (more powerful Intel Xeons).

Best regards,

Yvan

[Gareth_HHU]

Hello, Yvan

Thanks for your kindly reply!

It seems that Epyc2 (zen2 version) processors have higher memory bandwidth, which means it could make more cores play their abilities? Also, considering the budget, EPYC processors seem to have a better price / performance ratio.

All regards.

Gareth