[SOLVED] Windows VM Memory Full Issues

[Sheerpython]

Hello!

I have a Windows server 2019 VM setup with all the correct VIRTIO guest drivers installed (also ballooning) and its giving me some strange behavior.
Every time I boot the server the memory starts to fill up as shown in the images below.

Searching on the forum / google I could only find posts regarding the VIRTIO drivers and them not being installed, I repaired them but that didn't change anything.

Booting in safemode the problem still occurs

(Edit: this always happend, only server manager running)

Thanks for your help in advance!

 

[Sheerpython]

So i did some monitoring of the resource monitor in windows while in safemode and the first screenshot just after it booted and the second screenshot is from when it was using around 14 gb of ram. I don't know where the ram usage is coming from, the resource monitor also doesn't seem to know.

 

[Dunuin]

Maybe it is just the caching of Windows? With virtio and ballooning working Proxmoxs GUI will show RAM utilization without Win caching. If ballooning isn't working Windows cache will be shown as used RAM.

 

[Sheerpython]

Maybe it is just the caching of Windows? With virtio and ballooning working Proxmoxs GUI will show RAM utilization without Win caching. If ballooning isn't working Windows cache will be shown as used RAM.

The proxmox gui isn't the problem, even in the taskmaster and in the resource monitor it shows the ram high ram usage.

 

[Sheerpython]

Well after debugging and trying to get it to work for an entire day I just wiped the Windows VM and fully reinstall it. Seems to have fixed the problem, still no clue what caused it.

 

[SerVB]

Hi. I have the same problem and the same picture in both Windows Task Manager and Proxmox GUI. VirtIO drivers including balloon seem to be installed: when I run the VM, the RAM usage is low and after it becomes higher and higher (without VirtIO drivers, it was the maximum allowed for the VM right away from the start). Actually, it looks very much like caching because programs can be launched. However, some programs are "smart" and check the available RAM prior launching and say that there is no RAM for launching them.

Since I've just installed the VM, I'm not sure that after the reinstall everything will be fixed as for Sheerpython... Could somebody please help me localize the problem?

My best guess is that it's related to incorrectly installed drivers: maybe Windows installed some automatically before I installed VirtIO ones, so some of the latter weren't applied. Which drivers should I check?

Spoiler: Some screenshots of RAM usage and my configuration overall

UPD: moved here: https://forum.proxmox.com/threads/re-windows-vm-memory-full-issues.95357/.

 

[voarsh]

I am experiencing the same problems with a Win 10 VM..........

 

[xaifsystem]

i'm running win server 2019
same as memory usage high problem

 

[Zetto]

I have the same problem with Win11 VM. I gave it 16GB, to begin with and it maxed out. Because this was on the lower side I thought I give it another 8GB (24 total) but right after the boot it is at 98% usage again so something is wrong. Did anyone figure out what is going on? Proxmox is set to balloon between 4GB and 24GB.

 

[Dunuin]

Ballooning will only kick in once the hosts RAM usage exceeds 80%.

Every OS, including Win11, will eat all RAM you throw at it. If it doesn`t need it for programs, it will use it for caching.

How PVE will show the VMs RAM usage depends on if you usethe QEMU guest agent or not.

With QEMU guest agent: shown used RAM is "used" - "cache". What it is shows as "free" is actually not free but "available".
Without QEMU guest agent: shown used RAM is the real RAM usage by the KVM process, so RAM used for caching counts as used too. What it shows as free is the amount of RAM that actually is free (so not used by the guest at all).

 

[baxenko]

Same problem with Server 2021. RAM is 100% full in Windows, the server starts to lag.

Spoiler: baloon ON

As soon as I disable baloon in proxmox VM properties, RAM is freed immediately

Spoiler: baloon OFF

 

[why-be-banned]

same problem on my windows10 and windows11 VMs, I have to uninstall virtIO balloon driver to fix it.

 

[Marv21]

Gosh, that was a long Problem search. But i can confirm, i had the same...

 

[protocolnebula]

Same issue,
Tried with all display drivers, different virtio driver versions, still happening, no clue on what to do next

 

[jagtemp]

Experiencing the same with W7.

if all available RAM is being used by Windows as cache, then that's ok. However, the problem is it's making the system go slow.

Also, using RamMap, majority of usage shows as "Driver Locked":



What does that mean? It's locked by Ballooning driver and not usable by the VM?

 

[protocolnebula]

Fixed by my side:

- Missing in some machines virtio driver
- Ethernet card was not virtio, that caused issues
- Some additional hardware was not virtio (hard disk is an exception)

Also, all machines must a restart after apply the changes.

EDIT: NOT FIXED
It was working for a days, but randomly it crashed again (I did no update to the real machine).