Los Angeles1
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VMWare, vCPU allocation for VM
If I have a 16 core server, and I allocate only a single VM, and that VM is only allocated 8 vCPU, ......
... will that VM run with only 8 cores, or will VMWare detect that more cores are available and steal cores and give it to the VM, therefor that VM is running with more than 8 cores ?
Thanks
... will that VM run with only 8 cores, or will VMWare detect that more cores are available and steal cores and give it to the VM, therefor that VM is running with more than 8 cores ?
Thanks
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ASKER
Do the 2 posts above disagree. The first says the scheduler will use whatever it needs, (so I assume that the VM will use extra cores that are not being utilized, even if it exceeds the limit of vCPU assigned to it) the second says 8 vCPu means only 8 physical cores.
Am I misunderstanding your answers (I know you both generally agree, so I must misunderstand something)
Am I misunderstanding your answers (I know you both generally agree, so I must misunderstand something)
if you assign 8vCPUs, the hypervisor WILL ONLY ever execute your VM on 8 Cores.
(they may not be the same cores, through the process of the execution!)
e.g. the scheduler looks at ALL cores every 20ms, you VM may run on the same 8 Cores, or it could change to another 8 Cores, but by defination of 8vCPUs, it will never be more than this.
AND, if you do not have a license to use 32 vCPUs, license restricts you to 8 Way SMP.
(they may not be the same cores, through the process of the execution!)
e.g. the scheduler looks at ALL cores every 20ms, you VM may run on the same 8 Cores, or it could change to another 8 Cores, but by defination of 8vCPUs, it will never be more than this.
AND, if you do not have a license to use 32 vCPUs, license restricts you to 8 Way SMP.
http://www.vmware.com/files/pdf/techpaper/VMW_vSphere41_cpu_schedule_ESX.pdf
~coolsport00