open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello！

After the learning of TELEMAC,I want to buy a new computer for further work.So I want to know what computer characteristics are required for TELEMAC ?

I mainly use TELEMAC-3D and SISYPHE/GAIA modules, and a CFD software Code_Saturne (also developed by EDF) may be used later.

Thankful for all kind help!

Gareth

Hello Gareth,

The most important choice is CPU of course and budget plays an important role as their price ranges from a few hundred to many thousand...
In my experience with TELEMAC, if you are dealing with small domains, i.e. a few thousand nodes per core or less, then you should go for low core count, frequency optimized CPUs. Having too many, low frequency cores will not greatly speedup a single computation. However, you should be able to run 2 (or more) separate computations at the same time at reasonable speed. So, there is a trade-off there.

Intel is the leader in per thread performance, but quite expensive. AMD is getting better at it, especially with the upcoming Zen 3 architecture, and has greater value for money.

Costas

Hello cyamin！

Thanks for your reply.

I would like to deal with a large domain, which may have hundreds of thousands grids or even more. So does this mean the CPU with more cores (low frequency per core) will be better ?

The CPU based on Zen 3 architecture is not yet available. What do you think of AMD EPYC Processor(Zen 2 architecture)?

Best regards

Gareth

Well, the larger the partition, the lesser the communication overhead, so yes you will get better scaling of #CPUs vs runtime. But don't expect 64 cores will be twice as fast as 32 cores. Of course, this is also attributed by the way new CPUs throttle frequency based on thermal output. Running all cores reduces frequency per core.
I am running AMD EPYC (ZEN1) 24 core systems. I was not impressed by their performance compared to their XEON 16 core contemporaries on single computations. They usually do pretty well on coping with multiple ones though.
If you can wait a few months, wait for ZEN 3 or go for frequency optimised ZEN 2. You can also consider Ryzen TR as well. They should be very good for a single computation, but I don't know if the reduced memory bandwidth can pose a limitation at running multiple computations at once.

Costas

Thanks for your reply.

As I know, the reduced memory bandwidth will affect running multiple computations at once.Considering the overall needs of our group, multiple calculations may be performed simultaneously. So I would like to buy a CPU with more cores.

I saw on the forum that telemac does not support GPU acceleration at present, and there is no relevant development plan. Is it?

Best regards

Gareth

Hi Gareth,

Indeed, it does not support GPU acceleration atm but there is some research going on. There was a paper from Grasset et al in the 2019 TUC titled "Porting TELEMAC-MASCARET to OPENPOWER and experimenting GPU offloading to accelerate the TOMAWAC module".

Costas

Hello cyamin,

Thank you for your kind help!

Best wishes.

Gareth