Hyper-V VM settings
While within Hyper-V you can assign vCPUs to VMs, these vCPUs are effectively threads that compete with the threads of other VMs for resources.
Ciena recommend dedicated CPUs for the router so that the data plane gets cache hits and there is not continual in and out swapping of data when forwarding packets. Ciena recommend 1 CPU for every interface and 1 CPU for every control plane.
Ciena recommend the following settings for a router VM to make the vCPU in Hyper-V as close to a dedicated CPU as possible:
- VM reserve: 100
- VM limit: 100
- Relative weight: 10000
Vyatta also recommend that you switch hyperthreading off for the hypervisor.