Mastering Proxmox - Third Edition

Start small with VM resources

A virtual machine is completely different from a physical machine and it needs to be treated as such. They do not consume CPU and memory like a physical node does. The best practice is to always provision CPU and memory resources sparingly, and then increase them as you see the application's performance. This allows the VM to use allocated resources efficiently, which in turn makes all the VMs run efficiently in the node. By over-provisioning CPU and memory for all VMs in the node, we degrade node performance, because all VMs will be fighting to have more CPU time. Always start with one virtual CPU (vCPU) for most of the VMs. Start from two vCPUs for processor intensive VMs such as database servers, exchange ...