EVC with different core CPUs?

[Dhakshinamoorth]

Hi All,

My Cluster have four ESXi hosts with CPU model=Intel(R) Xeon(R) CPU E5645  @ 2.40GHz-6 Cores. I need to add our existing standalone HP DL380G6 servers into the same cluster. CPU model for the HP DL380G6 Server=Intel(R) Xeon(R) CPU E5530  @ 2.40GHz-4 Cores. I aware EVC suppress CPU instruction features from higher model and create the baseline for CPU features that are available in all CPUs and i don't know how EVC works with different CPU physical cores? Please suggest me.

[vGuy]

Although ideally you would want to have servers with similar config in the cluster, you should be able to configure EVC with no issues in this case.

[MKguy · Accepted solution]

EVC or vMotion compatibility in general doesn't care at all about the number of cores your physical CPUs have. The physical layout is completely hidden from the guest so it doesn't matter from a VMotion perspective if you mix 4, 6 or 8 core hosts in a cluster.

However, what really matters is the CPU generation and the respective instructions newer CPUs have equipped as opposed to previous ones.

Your Xeon 55xx CPUs belong to the Nehalem family, while the 56xx are part of the Westmere family. VMs running on the 56xx CPUs natively (no EVC configured) or with the Intel Westmere EVC baseline will not be able to be vMotioned onto the 55xx hosts.

So you will need to set the EVC baseline of your cluster to the Intel Nehalem generation.

Consult the following KB articles for more info.

http://kb.vmware.com/kb/1003212

http://kb.vmware.com/kb/1005764

http://kb.vmware.com/kb/1991