Build machine (compiling), VM sizing, NUMA 12vcpu, license

[vmmpa]

Hi,

system specs:

- 24C @ 2GHz Epyc (4 NUMA nodes)

- 128GB mem

- ESXi free license (8vcpu limit)

- 13 VMs (1-2 vcpu)

I need to create a build machine which benefits from lots of vcpus. Right

now i'm testing with a 6vcpu (fits into 1 NUMA node), 16GB memory

and when compiling, cpu0-5 are most of the time @90-100%

As i could use more vcpu for this machine (the software can handle it), i'm

planning to buy the Essential License to create a VM with 12vcpu (2 NUMA

nodes), but i'm not sure about the performance penalty because of going

from 1 -> 2 NUMA nodes.

Can you say (as a rule of thumb):

2 VMs with 6vcpu (1 NUMA node) are better/fast than 1 VM with 12vcpu (2 NUMA

nodes) even when the OS within the VM can drive 12vcpus?

Any recommendations appreciated.

Thanks, Mark

[vmmpa]

I've found sth interesting regarding my Epyc 7401P and ESXi 6.5 during my tests.

It seems that Turbo Boost isn't working correctly. According to AMD, the 7401P

should be able to drive 2.8GHz all core boost, but instead esxtop -> p shows

PSTATE MHZ: 2000 1600 1200

CPU %USED %UTIL %C0 %C1 %P0 %P1 %P2

Am i missing sth? I've checked the BIOS and "Core Performance Boost" is set to "Auto (default)".

https://www.supermicro.com/manuals/motherboard/EPYC7000/MNL-2085.pdf

[vmmpa]

Forget about my question above. Using esxtop -> p -> f (filter) -> F (%Aperf/%Mperf)

shows round about 140% for cores while compiling...and 1,4 x 2000MHz ~ 2800MHz

whichs matches AMDs infos.