Hyper-V Live Migration and CPU Allocation / Oversubscription
Still trying to wrap my head around all this Hyper-V stuff.
I've got two hosts, both dual-socketed with hexacore Xeons, so 12 cores/ 24 threads each, and 32GB of RAM. They'll operate in a failover cluster with live migration in case anything goes wrong.
I've got it planned so that the startup RAM for every VM totals 30Gb (leaving two for the host) so that in the case of a failover, one host can manage every VM. I'm then planning on using the dynamic memory to let VMs grow to a higher value when both hosts are up and there's 60Gb of RAM available to use overall.
However, I cannot, for the life of me, find out if I can do a similar thing with CPU cores. Does this mean I need to plan my core allocation to fit into the 22 available threads and waste half my processing power for a just-in-case scenario? Or will Hyper-V/VMM allow for CPU oversubscription, where in normal day-to-day activity there's no oversubscription taking place except when one host failsover? Potentially it's not as wasteful as it might seem as it would at least mean that VMs have real cores allocated rather than HyperThreaded Pretend Cores, except when failing over, but it still strikes me as under-utilising resources.
Has anyone set this up to know better than Google?