Any performance advantage of running a dual CPU setup when using under half of the cores?
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I have a Dell r630 with dual CPUs. I’m not utilising half of the cores and my question is whether it will have any performance difference if I remove one of the CPUs?
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@runevn What do you mean by half? Just for a VM?
Don't forget about Dom0. If you have dual 8 core and you have VMs with 8 cores assigned then you are using more than half because of Dom0. But if you are not using all of the CPU all of the time then performance could be worse but normally will not be worse with just one CPU.
Network uses CPU, disk uses CPU, management uses CPU, etc...
What about memory? With one CPU you only get 1/2 the memory slots and sometimes some PCI slots a tied to the second CPU.
If you have lots of cores and you pull a CPU then as long as you have enough processing power and memory for the VMs and Dom0 then performance might be better because everything runs on one node in the system (NUMA).
Why remove one CPU? Yes you can save some power.... Yes, a 22 core CPU is not free and you could build a second server (with lots of other parts).... but it would be better to just leave the hardware alone if it's working.
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@Andrew thanks for your reply. I have more than enough cores and memory slots for one CPU so I guess I’ll put one of the CPUs in the drawer.