mitch98

Update on my Windows 11 VM: It looks like I've been able to squeeze moderate performance out of a fresh Windows 11 VM now by using all of the tips outlined in this post as well as a few others that I will mention below. I suspect some of the issues I've experienced are due to a number of factors, one of which I suspect is the Windows Core Isolation setting in Windows Security. I have had a Windows 10 VM running for about a month now without any major issues and, while performance is not great, it's serviceable for my needs. The only difference I found between the VMs is that Windows Core Isolation setting being turned OFF on the Windows 10 VM (that is working) and turned ON in the Windows 11 VM that was experiencing issues. I also believe that Bitlocker drive encryption may be a contributing factor as I also tested migrating an existing Windows 11 Hyper-V VM (with Bitlocker enabled) to Unraid which worked but was met with the 100% CPU utilization problem again despite any tweaks I made. I could've tried turning off Bitlocker on the VM to see if it helped but I decided to leave that rabbit hole for another day. TL;DR: I think there are a lot of "gotchas" with regards to Windows VM performance in Unraid and it's not exactly straight-forward. I guess some of these could be mitigated by including the XML changes mentioned in this post in the Windows 11 VM template.

Thanks all for your responses, I'll keep looking at it and see how I go. Much appreciated.

I've been having the same issues and I am honestly about to kick the server over and just give up on self-hosting. This isn't my first rodeo with self-hosting (I've run XCP-ng, Hyper-V etc. in the past without a hitch and have been in the IT industry for many years so I've had exposure to all the big players) but it has by far been the most painful experience with getting VMs working. Docker containers? Works great in my testing so far. WebUI? Clean, relatively intuitive and responsive. Setting up SMB/NFS shares? Easy. Have had minimal issues. Running Linux VMs? No dramas at all from what I've seen. Running a Windows VM? No chance in my (albeit limited) experience on Unraid. The CPU in my Windows 11 VM is pegged at 100% while idling, with MS Edge consuming the most CPU (I don't believe that is accurate as Edge isn't even running, so it's just a background process.) It's a brand new install of Windows and I haven't even installed any apps. Host CPU util spikes to 100% on random cores. My system is an HP ML380 Gen 9 with an Intel Xeon E3-1240 v5, 64 GB of ECC RAM, 4 disks in my array (3 data 1 parity, two of the disks are spun down as I haven't filled up the array enough yet and I have idle spin-down enabled) plus a 500 GB SSD cache drive. This shouldn't be happening. Disk for the VM sits under /mnt/users/domains/<folder_for_vm> and I have the cache for the domains share set to Prefer: Cache I'm using virt-io for everything. I've installed the latest virt-io/KVM drivers on the VM. I implemented your fixes and it seemed to alleviate some of the burden on the host (Unraid shows slightly less CPU util and not across all cores now) but still the same, unusable performance results inside Windows. I'm not even trying to run a gaming VM or anything, it's more of a jump box/VDI for testing. Really disappointing, this might force me to move away from Unraid and just run a full XCP-ng/Xen Orchestra stack with a TrueNAS Scale VM and direct passthrough for my storage needs. This over-complicates my setup and locks me into ZFS along with it's ECC memory "requirements" (no one seems to have a straight answer as to whether it's a requirement or just strongly recommended. I have ECC RAM but my next server might not which limits my future expansion) ZFS/TrueNAS also have stricter disk requirements so I can't just slap in whatever I have laying around, not a concern for now as all my disks are the same (came with the server) but they are old and one's bound to fail soon, I don't intend on purchasing an OEM replacement direct from HP when I have a plethora of other 3.5" drives on hand. Not sure if this is an issue specific to the version of Unraid I am running (6.11.5) but it's a real shame as Unraid was gearing up to be the "all-in-one" solution that would've suited my environment well. Glad I'm only running the trial version but I've still poured more hours into configuring this than I should have given these results. Any advice from anyone would be appreciated as I'm about to pull the plug on the whole thing and go back to the drawing board.