I have a 2950x with cores 1-7 isolated for vm use. Clock speed is 4.2ghz. I have my vms on the 2 nvme cache drive in raid 0. MSI 1070ti

I am getting scrolling stutter in Divinity Original Sin enhanced edtion, grim dawn and also Torchlight.  No matter what I try i cannot resolve this.

Its a persistent stutter for a second or two when scrolling

 

I have tried:

Passing through a SSD and installing windows on that (thus avoiding a vdisk)

Various xml enhancements like raw rather than qcow2 and using SCSI as the driver

Tweaks to the CPU speed in terminal to set the min speed of cores 1-7 to 4.2ghz

Tweaks to nvidia settings - max performance, low latency setting on, vsync on, triple buffering on

tried cores 0-8

tried more cores, less cores

MSI interrupt fix

looked through the forums and googled and tried various other tweaks but no way is this near bare metal

 

Nothing else is on the server of consequence. Some dockers but nothing with heavy load.

 

I have a 6700k also and when I play DOS EE or the other games mentioned no stuttering

 

I am wondering if a) anyone else has this issue b) its a KVM bug as I have seen reports of gpu stutter with games

 

I truly am at my wits end, I dont want to give up on unraid for gaming but this issue is making these games unplayable

 

vm.xml and diagnostics attached

vm.xml bishop-diagnostics-20200908-1514.zip

Edited September 8, 20205 yr by AntaresUK

Hi, still learning my way in VM's but a couple of suggestions.

 

1) the XML suggests you are using cores 1,2,3,4 and the HT 17,18,19,20.  

If I understand correctly this would cross CCX's on threadripper or ryzen which can cause extra latency. 

Core 0,16 should always be left to unraid. 

Try 4,5,6,7 20,21,22,23

 

2) Your GPU pass through splits the GPU from a multifunction device into 2 devices in separate virtual PCI-E slots. 

This is my config with manual editing.

You can see the addition of " multifunction='on' " in the first pass through (video)

 

The next pass through (audio) has function='0X1' but has the same source and destination slots as above, it just uses the second function.

The source is the physical hardware, the address is the virtual hardware presented. 

In your case the audio is presented as "function=0x0" on a separate slot. 

      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0' multifunction='on'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x01' slot='0x00' function='0x1'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x1'/>
    </hostdev>

video here:

 

 

Thanks for responding @Decto, unfortunately that made no difference. I'll keep trying

Finally figured out what was causing the stutter. I had an all core overclock to 4.2ghz. Once this was taken off and MSI interrupts added no more stutter. I even was able to play DOS EE with g-sync on for the first time on unraid Oh happy day. Thought Id post the solution here in case anyone else is facing the same issue.

 

 No overclock, MSI interrupts, g-sync on and triple buffering = happy gamer finally

On 9/24/2020 at 1:05 AM, AntaresUK said:

Finally figured out what was causing the stutter. I had an all core overclock to 4.2ghz. Once this was taken off and MSI interrupts added no more stutter. I even was able to play DOS EE with g-sync on for the first time on unraid Oh happy day. Thought Id post the solution here in case anyone else is facing the same issue.

 

 No overclock, MSI interrupts, g-sync on and triple buffering = happy gamer finally

So disabling overclock fixes it?

I had a problem with My Gaming VM and micro freezes which took me almost 1 day of testing.

At the end the verdict was no pinning, no xml config, etc. It was my Corsair slipstream wireless USB Stick on a USB3 Hub or a single USB3 port. After I found out, that the freezes disappeared when I did not open Teamspeak client, I thought the Dongle. Binding the Dogle to one USB2 port and pass this through fixed the problem.

Lesson lesrned.

Edited December 27, 20205 yr by derpuma

1 hour ago, sonuyos said:

So disabling overclock fixes it?

So far, with passing through a nvme this is as close to bare metal as i have been able to reach

1 minute ago, AntaresUK said:

So far, with passing through a nvme this is as close to bare metal as i have been able to reach

Did you trying pinning?