Performance Issues After Upgrading to Windows Server 2022: Need Help!

This may sound odd, but if you've implemented all the other fixes and performance still lags, consider disabling Windows Defender. I've had instances where it hogged CPU resources extensively. You can limit its CPU usage through scripts if you decide to keep it running.

If you're running a vSAN environment, you might want to try disabling TRIM/UNMAP at the OS level. This adjustment helped us resolve several performance complaints across our 2019/2022 servers. Just remember to periodically re-enable it if you need to manage space.

My guess is that with 32 vCPUs assigned to each VM, you might run into high CPU ready issues, especially if there are other VMs consuming resources. It makes sense since you previously had one VM running with much less power and no complaints.
Just something to keep in mind!

Expecting performance to match what you had on 2012 without upgrading hardware is unrealistic. Performance usually degrades with new versions, and a drop of around 50% is not unheard of when comparing 2012 to 2022. With better hardware and lower user loads, your performance should improve significantly.

Another thing to check is whether all virtual CPUs are properly assigned to the same physical CPU. NUMA configuration can really impact performance, so ensure it's set up correctly.

Here are some things I would check:
1. Monitor storage latency and ensure it doesn't exceed 4ms.
2. Look into the CPU ready time as it might be too high; tweaking the core-to-socket ratio could help.
3. Make sure your antivirus is configured properly, particularly for exclusions related to critical processes.
4. Check out this link for issues related to long login times or black screens: [Link](https://www.phy2vir.com/windows-server-2016-2019-rds-server-black-screen-or-start-menu-not-working/#google_vignette).
5. Remember that Windows Server 2022 uses fair share features—disabling that may not be advisable.

Just bumping up resources doesn’t guarantee better performance. You might want to consider scaling back your CPU allocation to what you used previously and see if there's an improvement. Overloading the hypervisor with 32 cores can lead to performance bottlenecks, especially if other VMs are competing for those resources. Also, keep an eye on the NUMA configuration and ensure the VM's settings are aligned with Windows Server 2022's requirements.