#VCP #Concept Sets the CPU Generation to one level inside an EVC enabled cluster. This will restrict newer CPU Generations to use instruction sets from the newer Generations that are not included inside the set Generation. This will generally result in a small decrease in efficiency/performance if an application running on a VM is utilizing instructions from the newer generation. This is usually pretty unlikely though. ## Changing the EVC mode of a Cluster ### Prerequsites - All hosts in the cluster must have a supported CPU for the EVC mode. - All hosts must be connected and registered - If EVC mode is downgraded VMs need to be in a shutdown state before downgrading EVC mode ### Downgrading EVC mode 1. Power off any higher EVC mode VMs 2. Check and select the desired CPU generation 3. change EVC Mode of cluster ### Upgrading EVC mode 1. Check for compatibility of all hosts 2. Check and select the desired CPU generation 3. Change EVC mode of cluster 4. (optionally) set VM parameter `vmx.reboot.powerCycle` to true, so the VMs will reset properly and are upgraded to the newest EVC mode once they are restarted The VMs that were previously on a lower EVC mode will only be upgraded to the newer mode once they are completely shutdown/powercycled. ## 🔗Resources ### EVC FAQ https://knowledge.broadcom.com/external/article/313545/vmware-evc-and-cpu-compatibility-faq.html ### EVC Mode Documentation https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.vm_admin.doc/GUID-A1C095EF-1B0F-4C10-9190-CFDD07193B2B.html