Proxmox 6 and windows 2008 not R2 server


Renowned Member
Apr 15, 2011
Hello everybody.

Recently I have migrate my production cluster from proxmox 5 to 6.

My actual version is
pveversion -v
proxmox-ve: 6.0-2 (running kernel: 5.0.18-1-pve)
pve-manager: 6.0-5 (running version: 6.0-5/f8a710d7)
pve-kernel-5.0: 6.0-6
pve-kernel-helper: 6.0-6
pve-kernel-4.15: 5.4-6
pve-kernel-5.0.18-1-pve: 5.0.18-2
pve-kernel-5.0.15-1-pve: 5.0.15-1
pve-kernel-4.15.18-18-pve: 4.15.18-44
pve-kernel-4.13.13-5-pve: 4.13.13-38
pve-kernel-4.13.13-4-pve: 4.13.13-35
pve-kernel-4.13.13-2-pve: 4.13.13-33
ceph: 12.2.12-pve1
ceph-fuse: 12.2.12-pve1
corosync: 3.0.2-pve2
criu: 3.11-3
glusterfs-client: 5.5-3
ksm-control-daemon: 1.3-1
libjs-extjs: 6.0.1-10
libknet1: 1.10-pve1
libpve-access-control: 6.0-2
libpve-apiclient-perl: 3.0-2
libpve-common-perl: 6.0-3
libpve-guest-common-perl: 3.0-1
libpve-http-server-perl: 3.0-2
libpve-storage-perl: 6.0-7
libqb0: 1.0.5-1
lvm2: 2.03.02-pve3
lxc-pve: 3.1.0-61
lxcfs: 3.0.3-pve60
novnc-pve: 1.0.0-60
proxmox-mini-journalreader: 1.1-1
proxmox-widget-toolkit: 2.0-5
pve-cluster: 6.0-4
pve-container: 3.0-5
pve-docs: 6.0-4
pve-edk2-firmware: 2.20190614-1
pve-firewall: 4.0-6
pve-firmware: 3.0-2
pve-ha-manager: 3.0-2
pve-i18n: 2.0-2
pve-qemu-kvm: 4.0.0-5
pve-xtermjs: 3.13.2-1
qemu-server: 6.0-7
smartmontools: 7.0-pve2
spiceterm: 3.1-1
vncterm: 1.6-1
zfsutils-linux: 0.8.1-pve1

All work fine except 2 windows 2008 not R2 version.

These machines consume a huge quantity of CPU normaly less then 10% and now more then 60%.
These machines has also a huge time drift nearly 1 min real time = 4 mins on vm time.

For example this on configuration file

cat /etc/pve/qemu-server/203.conf
agent: 1
balloon: 0
bootdisk: scsi0
cores: 8
ide2: rackstation_cluster:iso/virtio-win-0.1.171.iso,media=cdrom,size=363020K
keyboard: fr-be
machine: q35
memory: 10240
name: STESUD06
net1: e1000=96:7B:C2:21:CA:18,bridge=vmbr0
numa: 1
ostype: w2k8
scsi0: vm_storage:vm-203-disk-0,aio=threads,cache=writeback,size=90G
scsihw: virtio-scsi-pci
sockets: 1

I try to had args : -no-hpet in this files and nothing change

Is anyone has an idea where the problem come from ?
I think that I find something in the qemu 4.0 documentation? I modify a clone VM conf file like this

args: -rtc base=localtime,clock=vm,driftfix=none

And it seem to work normaly.

I keep you informed of futher evolution during the week
After installing a new Win2008r2 VM on a Proxmox 6.0-4 server, the VM time was mad fast (6 seconds realtime == 60 seconds VM time!). Your instructions seem to have solve the problem.

For the record: the default values seem to be -rtc 'driftfix=slew,base=localtime'.
This seems to work too: args:
-rtc base=localtime,driftfix=none.


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