Single or Dual CPU Hosts - Any reasons to choose one over the other?
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Re: Any performance advantage of running a dual CPU setup when using under half of the cores?
We are reviewing our system design and have the option to purchase new Dell systems. We are considering a single CPU system 6615 with an Epyc 9354 (3.25 GHz with 256M Cache) - and a dual CPU system 6625 with dual EPYC 9124 (3.0 GHz with 64M Cache). All other specs are the same. The number of VMs and the loads on the CPUs can run in either system, and we are not constrained by memory requirements. The decision comes down to about a $1K difference per host. The environment consists of 3 hosts, so $3K difference. I am open to all opinions and welcome your thoughts.
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@Bill.Oliver obvioulsy, licensing.
If you are planning to put Microsoft VMs, beware of licensing with multisockets by hosts, you have to cover them all.
By default, you should cover 16 cores with 1 Microsoft Windows Server Standard to get 2 VMs licensed.
If you get two sockets, you have to double the licensing (and add 2 packs core to attain your cores coverage...)All licensing based on cores make you think twice when planning CPUs...
If you want to, you can go DATACENTER edition, but you still have to cover all the cores...
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@Pilow, this is very true. I should have been a little more specific. The two options we are considering are a 32-core single CPU and dual 16-core CPUs. So, the total core count is the same.
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@Bill.Oliver license-wise should be the same.
now I think virtualisation gurus here could try to explain you what are the challenges with numa and dual sockets
i have notions, but couldnt explain quite the optimisation in xen