We did a benchmark of our software on the mentioned processor. There i noted that compiling with different versions of gcc resulted in different openmp performance (numbers given are min in time to complete the code):
| AMD (128 cores) | ||
| gfortran 10 | 5.8 | |
| gfortran 11 | 8.7 | |
| gfortran 12 | 11.3 | |
| gfortran 13 | 12.5 |
The strange thing is that gfortran 10 is performing better than the later versions.
Is there a problem with recognizing the CPU? The code does not support GPU.
Can i add an additional flag in the later gfortran versions to improve the performance in the later gfortran versions?
In terms of scaleup the gfortran 12 and 10 are similar on AMD, in terms of speedup there is a big difference:
(This is a copy of the thread in: drivers and software: https://community.amd.com/t5/drivers-software/gcc-and-fopenmp-on-epyc-9654-and-epyc-9754/m-p/669053#...
