Hi , .
hope everybody is well
I am calculating cpu ratio in my cluster and use this :
(Get-cluster -name MyCluster | Get-vm | Where Powerstate -eq “PoweredOn” | Measure NumCpu -sum).sum / (((Get-cluster -name MyCluster | Get-vmhost).extensiondata.summary.hardware | Measure -Property numCpuCores -Sum).sum)
but I am not sure should second part of command multiply with 2 because hyper-threading is enabled, because hyper-threading only increase performance by 30% , don actually increase number of CPUs
Moderator: Thread moved to the PowerCLI area.
It is a matter of preference.
Most ratios I calculate use in fact the NumCpuThreads property in the Hardware object.
That means that HT is taken into account.
I often provide both, 'CPU Ratio', where I use NumCpuCores, and 'HT Ratio', where I use NumCpuThreads.
But remember that rules of thumb based on ratios are not absolute.
As always, it depends.
Measure what your VM is actually doing (CPU Ready is a good indicator), try to find variations over time, and many more aspects.
if calculating CPU radio I use NumCpuThreads the result is 6:1 and I need to add more power to the cluster, but if I use NumCpuThreads then is 3:1 them there is no need for expansion. that is what is confusing me