Windows Guest Balloon issue?

[lucidnx]

Hello! I am facing issue with memory being "Driver locked" in Windows Server 2022 and Windows 11 Guest (not all, just 3VM's of 6). After boot, RAM is growing up to maximum, it does not matter how much RAM I assign to VM.

Host: Proxmox VE 7.4-3
MB: Asrock Rack X570D4U-2L2T
RAM: 4x32GB Kingston 3200MHz ECC
FS: ZFS Mirror (2x1TB NVMe Kingston KC3000)
FS: ZFS zRAID2 (6x16TB Toshiba MG08)

ZFS is using 64GB of RAM as cache, 18GB is free and rest of it is used by VM's. I have tried to shut down some unnecessary VM's to release more RAM, without luck.
VM's are all on latest virtio drivers, 0.1.229-1

This is screenshot from WS 2022, almost whole memory is being Driver Locked:



Proxmox GUI:


this is from another Windows Server 2022 VM used for RDS:



What does "Driver Locked" mean and why is this happening?

 

[IvanF]

Hello. reinstall/repair virtio-win drivers and guest agent can help you.
Similar post from yesterday. https://forum.proxmox.com/threads/inconsistency-in-reported-cpu-usage-windows11-vs-proxmox.125149/

 

[lucidnx]

Reinstalling did not helped at all. It may be some windows library as you mentioned, hope there will be quick fix for that...

 

[solv]

I'm running into this issue as well. I thought I had solved it when I updated to the .229 virtio balloon driver.
It stopped the RAM from filling up initially and the 'driver locked' process was not taking up any memory.
But this morning they are back up to ~70% and I believe the issue is to do with proxmox backup doing snapshots with a ZFS backed pool.
This thread here talks about the ZFS issue: https://forum.proxmox.com/threads/ballooning-memory-and-zfs-fighting-for-available-ram.88670/

I saw it also on reddit regarding ZFS arc causing a problem with memory ballooning.
Anyhow, for the moment I'm just going to have to disable it which is dissapointing.

 

[lucidnx]

I'm running into this issue as well. I thought I had solved it when I updated to the .229 virtio balloon driver.
It stopped the RAM from filling up initially and the 'driver locked' process was not taking up any memory.
But this morning they are back up to ~70% and I believe the issue is to do with proxmox backup doing snapshots with a ZFS backed pool.
This thread here talks about the ZFS issue: https://forum.proxmox.com/threads/ballooning-memory-and-zfs-fighting-for-available-ram.88670/

I saw it also on reddit regarding ZFS arc causing a problem with memory ballooning.
Anyhow, for the moment I'm just going to have to disable it which is dissapointing.

This may be it.. but why is it "driver locked" in windows and shown as full in proxmox? linux VMs are unaffected (I don't see RAM full, even in VM it is fine)

 

[solv]

This may be it.. but why is it "driver locked" in windows and shown as full in proxmox? linux VMs are unaffected (I don't see RAM full, even in VM it is fine)

I'm guessing only in a windows VM because it's specific to the virtio memory driver for windows guests, but couldn't really say that for sure - above my level of understanding unfortunately

 

[_gabriel]

no pcie passthrough ?

 

[edurbs]

I had the same problem (without pcie passthrough) with Windows Server VM (2019 and 2022).
To solve it, I had to disable ballooning feature.

 

[lucidnx]

no pcie passthrough ?

I have GPU assigned to one of VMs but there is no balloon used. Issue is affecting other VMs.

 

[leesteken]

I have GPU assigned to one of VMs but there is no balloon used. Issue is affecting other VMs.

Ballooning cannot work with PCIe passthrough, but you can use it with memory hotplug.

EDIT: I misunderstood, sorry.

 

[lucidnx]

Ballooning cannot work with PCIe passthrough, but you can use it with memory hotplug.

I know, that's why I wrote that. just in case it is related anyway.

 

[andmattia]

I have the same issue on all VM on AMD process. I stop ballon service and ram usage switch from 95/98%.

Is it normal?

Which impact could be happen with ballon disable?