Windows 10 VM poor performance, 100% CPU after 6.9 upgrade

[NerdyGriffin]

2 hours ago, jonathanm said:

Try reducing the number of cores assigned to the VM so the emulator has more power available.

I tried that, in various configurations, but it actually made the problems worse in the VM.

 

I was actually using it with 6 cores for many months before the update to 6.9, and then the performance problems started after the 6.9 update so I tried reducing the load from everything else (turn off extra VMs, turn off extra dockers, limit docker cpu usage, pin docker cpu cores to leave more unused cores for the host OS, etc.) so that I could rebalance things enough to give the Windows VM more cores.

 

In 6.8, it was perfectly smooth with 6 cores,

but now in 6.9 the VM runs so bad with 6 cores that it is completely unusable for daily work, and with 8 cores it is slightly better but nowhere near what it performed when I was using Unraid 6.8

[NerdyGriffin]

On 5/6/2021 at 10:36 PM, NerdyGriffin said:

but if I move the mouse around it freezes/stutters...

I tried various changed to VM settings, nothing has made any difference yet, but I did try turning down the polling rate of the mouse and it improved the in-game issues, not improved to a playable extent, but the drop in performance is less dramatic. (Importantly, that is only in-game issues. The issues seen on the desktop with "normal" programs are completely unchanged by that, so there is some other root cause)

I also noticed that the CPU usage reported in task manager drops from 60% to below 30% during the moments of the in-game lag, so I would guess that means something is stuck "waiting" an abnormal amount of time for I/O things for some reason

[SimonF]

Which machine type and BIOS are you using on the VM

[NerdyGriffin]

13 hours ago, SimonF said:

Which machine type and BIOS are you using on the VM

I am using OVMF and i440fx-## [whatever the highest version number is in the list]

[NerdyGriffin]

Last night I decided to give-in and downgrade back to 6.8.3, and I posted some stuff here about it, but I will try to keep the performance troubleshooting discussion in this thread since to other thread is specifically about the downgrade process

 

I have not tried running games yet, but I can already tell that after the downgrade, I am already seeing a huge improvement in performance just in the Unraid GUI mode, and the webUI in general. The entire webUI experience was super laggy for me after upgrading to 6.9, so the issue was not just VM performance, it was all of Unraid performing poorly for some reason. 

As I mentioned in the linked comment, even just the startup-login screen of the Windows VM was super responsive, whereas with Unraid 6.9 that Windows login screen was laggy and typing in the password had a huge delay before it would actually show the inputs on screen. It never missed a keypress along the way, so everything was getting recieved and processed correctly eventually, it was basically just absurd CPU or I/O latency across the board, and I have no idea why

 

If it continues to run smoothly in version 6.8 after more testing, then I guess I will leave it at that version until I have more free time to be able to try upgrading again and troubleshooting, (otherwise it will have to wait until I can afford to buy or build another computer, at which point I likely will leave the current one as Unraid and use the new one as a normal desktop/workstation)

 

 

However, @SimonF, feel free to ask additional questions about the setup, either the current state or the state of it before the downgrade, because I have backups of all the config files and the VM xml files, taken before the upgrade, after the upgrade, after troubleshooting, etc. (I made backups a few times a month after upgrading to 6.9 because I was experimenting and trying different setting so much that I didn't want to forget what things I had changed or what config I had started with before tinkering)

On that note, let me know if you want me to share any of those XML files, if it helps in any way

[NerdyGriffin]

As a small update: After downgrading to 6.8.3, the performance of everything is much much better than it was before, so I don't know if or how that helps, but clearly the issues I have been having are related to something that changes in 6.9.x. 

 

While I do love the new features added in 6.9, I guess I will now be sticking around in 6.8.3, at least until I can figure out what was wrong or until I get way too curious and try experimenting again

[nukeman]

There's been lots of responses since I started this post and I thought I'd provide the group an update.  After changing my CPU Scaling Governor to "On Demand" the stability of my system improved dramatically.  I could install the Ubuntu Desktop VM and its performance is acceptable.  Also, the CPU use in the dashboard isn't spiking like it was previously.  Sounds like the CPU Scaling Governor setting hasn't fixed this for everyone, but it seems to be working for me.

[MrAndyBurns]

On 3/6/2021 at 1:02 PM, stor44 said:

Hi all. I had this problem too after upgrading to 6.9 this week. My Win10 VM and even unRAID itself were running dog slow. System Interrupts was using 100% CPU in Windows.

For me what worked was changing a setting in the "Tips and Tweaks" plugin. I had "CPU Scaling Governor:" set to "Power Save", which I think is the default for Intel CPU. Changed it to "On Demand", and now my VM and unRAID are running much better.

Disclaimer: I don't understand much of that, but it seems to work. Maybe there's downsides. YMMV. Seeing a lot of posts with this issue, hopefully this helps you.

Thank You @stor44!! ... after spending ages getting an Xpenology VM to run on the new 6.9.x, I merrily skipped over to my Windows VM and was gutted to find Windows running like it was on an old Atom notebook! It would have taken me ages to find the Tips and Tricks performance had changed! Thanks for the pointer, the initial testing looks good! (simple VM, RDC into Win11 developer build with allocated 2 core 4 thread 8gb hosted on i7-4790)

 

 

[Jawalking]

Decided to check if these performance issues still exist on 6.10 rc2, and they do... I'm gonna be stuck on 6.8.3 forever

 

[fearlessknight]

22 minutes ago, Jawalking said:

Decided to check if these performance issues still exist on 6.10 rc2, and they do... I'm gonna be stuck on 6.8.3 forever

 

Turns out my VM was just bad. After rebuilding from scratch everything including the CPU usage and idle was operating smoothly. Running on 6.9.2. Have you tried a fresh rebuild of the VM? I also disabled  system updates and just have whatever came on the Windows 10 image. Could possibly be a Microsoft update. 

Edited January 11, 2022 by fearlessknight

[Jawalking]

On 1/11/2022 at 4:19 PM, fearlessknight said:

Turns out my VM was just bad. After rebuilding from scratch everything including the CPU usage and idle was operating smoothly. Running on 6.9.2. Have you tried a fresh rebuild of the VM? I also disabled  system updates and just have whatever came on the Windows 10 image. Could possibly be a Microsoft update. 

 

Forgot to update, last night after having 6.10rc2 on there I decided to install win11 just to see. and everything works as expected. So yeah that's the trick, re-install windows.