W11 VM performance problem for RDP

[tyger81]

Hello,

I'm having a performance issue with my Windows 11 VMs; they're not running smoothly. Let me explain. I created a basic configuration:

6 vCPUs (with Numa active)

8 GB of RAM (I tested with ballooning and nothing changed. What's the point?)

160 GB of my Ceph storage (writeback cache, IOTread, IO_uring)

vmxnet3 (limited to 100 MB/s)

vGPU Tesla-P4 1 GB

Infrastructure configuration:

40 GB/s switch
3x R630
- 2x E5-2680V4
- 256 GB DDR4 RAM ECC 2133
PCi
- Mellanox 40 Gb/s
- Tesla P4

2x SSD SAS PM1643 960 GB in OSD

It's a Dell R730XD used for backup storage.

What are the settings or configurations that would be most optimized for VMs in Win 11 (this serves as a remote desktop in RDP) on it there is an office use, mail, youtube, ....)

 

[SteveITS]

6 CPUs or 6 cores? Try 6 cores, 1 CPU, if you don't actually have 6 physical CPUs.

What is the actual issue observed?

From what I've read ballooning is slower on Windows. The goal is to reduce memory usage in VMs if the host goes over 80% (by default) RAM usage.

 

[tyger81]

6 cores

I have 256 GB per server, so I've planned large enough to disable bloat. Will this reduce latency?

When I try to open an application, it takes several seconds to respond.


A test I ran:

When I quickly move a window in my VM (a Windows Explorer window) to the host's Htop, my CPU usage goes up to 600%, then drops back down. I know I'm constantly between 100 and 120% on the CPU. If I understand correctly, this corresponds to 100% = 1 core.

I ran a test with 16 cores, and I get to 1200% on the host.

 

[SteveITS]

I would disable NUMA in the VM, if you have one physical CPU.

You hit that CPU usage just moving an application window around? A couple months ago we set up several Windows 11 VMs for a client's remote staff, and have not had a report like that. Dragging windows sounds like a video driver problem.

Did you install the latest Virtio drivers?

 

[tyger81]

I have 2 Intel xeon E5-2680 V4 per server and a Vgpu from my tesla P4 of 1Gb I have no graphics part other than the tesla

ps: on a VM without nvidia, with virtio gpu same problem

 

[_gabriel]

switch vCpu type to x86-64-v2-aes
to prevent nested virtualization
enabled by default since Windows 11 version 24h2 with their VBS.

 

[tyger81]

no advantage to leaving in host mode?

ps:
I set "x86-64-v2-aes." It already seems smoother, but why?

I added vGPUs for graphics acceleration, but I don't see any significant difference in performance on the test host. There are only two VMs on it for testing.

https://passmark.com/baselines/V11/display.php?id=275368812124

 

[_gabriel]

It already seems smoother, but why?

because

nested virtualization
enabled by default since Windows 11 version 24h2

 

[SteveITS]

For reference

Thread
Thread
Thread

 

[tyger81]

For reference

Thread
Thread
Thread

I looked a bit but I didn't find it, thanks
another question
while I'm here, what are the best profiles for vgpu?

1B
1Q
1A

thanks in advance

 

[SteveITS]

No worries, the CPU is counterintuitive and also there's still a lot of advice online to use "host" for faster CPU. Can't help with the GPU question, sorry.

 

[tyger81]

That's already a lot of what you've done, when you have a vgpu you have to deactivate the integrated display and leave only the gpu or not?