Windows server 2019 performance is very bad

I am struggling with the windows server 2019 performance. Can anyone please suggest on how to improve the performance of windows server in Opennebula v6.4.2 and platform is Centos 7.9? All of my Linux VM are performing fine.

Thank you.

I have often found, manually creating multiple page files across all the disks give a performance jump.

That has often worked on physical machines, not sure it will on a VM

It is not clear what performance you are looking for - disk performance like throughput and latency, virtual desktop interaction latency, etc.

There are a lot of options for Windows VM performance tuning that are generic for any KVM solution.

Hint - get familiar what is the bottleneck you are facing, and what could be resolved by the Hyperv Enlightenments for KVM.

Some of them are already implemented in OpenNebula, others could be added via the OpenNebula RAW section for example.

Hope this helps.