Mixed host size cluster with big VMs

[CurtisGrice]

I have inherited an environment that's running well enough but we keep getting requests for 10-20 vPCs (I know we need proper VDI) at a time. I already saw CPU readiness start spiking 6-7% and don't want to see it go further.

On paper we have the resources but out of 12 hosts, 4 have 88 logical cores and 6 have 24 logical cores. We also have a hand full of "large" VMs with 12-16 cores. The issue seems to be that DRS keeps placing the big VMs on the small hosts.

Would I make sense to setup affinity rules so the larger VMs prefer the Large hosts and let the dozens of 2-4 core vPCs thrash the smaller hosts?

[scott28tt]

@CurtisGrice 

Moderator: Moved to vMotion & Resource Management Discussions

[ashilkrishnan]

Hi @CurtisGrice ,

If the requirement is to keep certain VMs on specific set of hosts, yes affinity rules will let you achieve this. You can create a group for hosts, VMs and configure rules to ensure these VMs must run on hosts in DRS group.

VM-Host Affinity Rules 

Hope that helps