Hi Forza

I run a few linux HPC clusters, one particular platform runs on XCP-ng VMs using AMD epycs. We see a max of 64 vcpus recognised by the VM on XCP. You can assign more, but they are not visible from the VM OS. There also seems to be a total RAM size per VM too, which is 512GB, if memory serves (no pun intended ).

With regard to your other question - 7773X vs 7204 - on linux I would suspect that most codes would run the same binaries on both, but you may see a performance hit if an optimized binary wasn't compiled against one or the other cpu. But of course, there could just as easily be lots of other reasons for differences in performance across these boxes.

Forza , Virtualization is PVHVM, running RockyLinux8. VM root disk is local to the host on RAID10 SAS drives, CPUs are dual-socket AMD EPYC 7552 48C/96T, and 512GB physical RAM. And no GPU.

Flexibility is prioritised over performance on this cluster - it's used for undergraduate teaching and projects. We don't do cpu-pinning for instance.

We typically run bioinformatics and Molecular Dynamics codes. If we look at MD codes (high CPU, low RAM , low IO), they scale as expected up to 64 cores - I'm pretty happy with the performance. But having said that, I haven't compared directly with bare-metal.

Forza , Virtualization is PVHVM, running RockyLinux8. VM root disk is local to the host on RAID10 SAS drives, CPUs are dual-socket AMD EPYC 7552 48C/96T, and 512GB physical RAM. And no GPU.

Flexibility is prioritised over performance on this cluster - it's used for undergraduate teaching and projects. We don't do cpu-pinning for instance.

We typically run bioinformatics and Molecular Dynamics codes. If we look at MD codes (high CPU, low RAM , low IO), they scale as expected up to 64 cores - I'm pretty happy with the performance. But having said that, I haven't compared directly with bare-metal.

Hi Forza

I run a few linux HPC clusters, one particular platform runs on XCP-ng VMs using AMD epycs. We see a max of 64 vcpus recognised by the VM on XCP. You can assign more, but they are not visible from the VM OS. There also seems to be a total RAM size per VM too, which is 512GB, if memory serves (no pun intended ).

With regard to your other question - 7773X vs 7204 - on linux I would suspect that most codes would run the same binaries on both, but you may see a performance hit if an optimized binary wasn't compiled against one or the other cpu. But of course, there could just as easily be lots of other reasons for differences in performance across these boxes.