[eric]

** Update 2: I have created a page on the OpenFOAM wiki: https://openfoamwiki.net/index.php/Benchmarks . The updated plot will now be found there as I will eventually not be able to edit this post. But please continue to contribute further benchmarks in this thread! **

** Update: I have now added a plot with minimum time to solution for all hardware posted in this thread! I will try to keep this updated as more results are posted. Thank you for all the contributions! **

Hi,

I promised in another thread here to run some OpenFOAM benchmarks on different Intel hardware that I have available, so here they are. These are based on the motorBike benchmark, but I modified it to have more grid cells, run fewer iterations and to use scotch decomposition. You can find the full setup in the attached tar.gz-file. If you want to test on your hardware, you only need to run the run.sh script (you only need to change the number of cores in the three for loops if you want to run on a different number of cores). It would be interesting if more people could contribute to generate a modest database of benchmarks here.

The below table shows runtime in seconds. There is also a graph which shows the speedup.

Some observations, most relatively obvious :

• There is an obvious correlation between speedup and number of memory controllers available. The old octocore E7 machine is very slow on single-core but shows great speedup. The other machines show modest speedup past ~2x the number of memory controllers.
• A fast CPU helps for single-core simulations. The two processors with 3.7 GHz turbo frequency are the fastest here.
• If you are buying new hardware, the Gold 6148 does not scale at all past ~16 cores so the 6130 or 6142 seem like better choices. Of course, this assumes you only have Intel available, if not AMD Epyc seems like a better choice based on the other threads in this forum.

#   Gold 6148  8x E7-8870  2x E5-2695 v2  2x E5-2643 v3  2x E5-2695 v4
1       874       2132        1451             883            1084
2       435       1124         597             468             578
4       225        476         281             215             273
6       164        297         205             153             189
8       136        203         178             126             146
12      111        148         150             101             104
16      101        104         140                              85
20       98         92         137                              76
24                  77         137                              71
36                  64                                          65

---MODERATOR NOTE---
The original bench template requires some tweaks in order to work with more recent versions of OpenFOAM. Try using bench_template_v02 for the openfoam.org versions instead, courtesy of Simbelmynë
For the openfoam.com versions (e.g. v2112) this script should work out of the box: OpenFOAM benchmarks on various hardware
bench_template_v02.zip

Newer performance charts provided by naffrancois with much more entries
Maximum performance: https://ibb.co/MsQh94V
Single-core performance: https://ibb.co/GVnbYP5
MS Excel file with the numbers: bdd_cpu_cfdonline.xlsx