Snapshot causes VM to become unresponsive.

[nivek1612]

I am not exactly sure when this problem first started but it used to be fine in the past
I'm running 8.2.4 of Proxmox, and I'm seeing strange behaviour of a VM post Snapshot.

I have an instance of HomeAssistant in a VM that after a snapshot is taken of it becomes very slow/non-responsive.
Stopping and starting the VM returns it to normal working mode

Any logs I can look at to find out what the problem is

I asked on the HomeAssiatnt Forum and some other people have similar issues.

 

[LnxBil]

Did you create the snapshot with memory? If so, try without.

 

[nivek1612]

I did and will try without

 

[nivek1612]

Without RAM avoids the issue. The question is why did it used to work ok

 

[lassiko]

Same issue here. Running 8.2.4 but this was happening before i updated current version.
Haven't tried snapshot yet without memory, but even it would work, as @nivek1612 is asking; what could be the root cause for this as it used to work fine? How to debug this issue? Thanks.

 

[mdavis06]

Experiencing the exact same issue. Used to work perfectly (with RAM), but now it doesn't. Looking for a solution or reason.

 

[fiona]

Hi,
please share the VM configuration qm config <ID> and the output of pveversion -v. What physical CPU do you have? Is there anything in the system logs?

EDIT: What guest (and kernel) is running inside the VMs? How does the CPU usage look like?

 

[nivek1612]

root@pve2:~# qm config 105
agent: 1
bios: ovmf
boot: order=scsi0
cores: 2
description: <div align='center'><img src='https%3A//avatars.githubusercontent.com/u/13844975?s=200&v=4'/></a>%0A%0A%0A # Home Assistant VM
efidisk0: local-lvm:vm-105-disk-0,efitype=4m,size=4M
localtime: 1
memory: 4096
meta: creation-qemu=7.1.0,ctime=1675622700
name: haos9.5
net0: virtio=02:79:26:B8:85:35,bridge=vmbr2
onboot: 1
ostype: l26
parent: precloud2
scsi0: local-lvm:vm-105-disk-1,discard=on,size=32G,ssd=1
scsihw: virtio-scsi-pci
smbios1: uuid=9f8174c5-5c21-4b70-a5c8-d9877470963d
tablet: 0
tags:
usb0: host=10c4:ea60
vmgenid: d153564f-5434-4446-a861-6d880e44dcdc


proxmox-ve: 8.2.0 (running kernel: 6.8.12-1-pve)
pve-manager: 8.2.4 (running version: 8.2.4/faa83925c9641325)
proxmox-kernel-helper: 8.1.0
proxmox-kernel-6.8: 6.8.12-1
proxmox-kernel-6.8.12-1-pve-signed: 6.8.12-1
proxmox-kernel-6.8.4-2-pve-signed: 6.8.4-2
ceph-fuse: 17.2.7-pve3
corosync: 3.1.7-pve3
criu: 3.17.1-2
glusterfs-client: 10.3-5
ifupdown2: 3.2.0-1+pmx9
ksm-control-daemon: 1.5-1
libjs-extjs: 7.0.0-4
libknet1: 1.28-pve1
libproxmox-acme-perl: 1.5.1
libproxmox-backup-qemu0: 1.4.1
libproxmox-rs-perl: 0.3.3
libpve-access-control: 8.1.4
libpve-apiclient-perl: 3.3.2
libpve-cluster-api-perl: 8.0.7
libpve-cluster-perl: 8.0.7
libpve-common-perl: 8.2.2
libpve-guest-common-perl: 5.1.4
libpve-http-server-perl: 5.1.0
libpve-network-perl: 0.9.8
libpve-rs-perl: 0.8.9
libpve-storage-perl: 8.2.3
libspice-server1: 0.15.1-1
lvm2: 2.03.16-2
lxc-pve: 6.0.0-1
lxcfs: 6.0.0-pve2
novnc-pve: 1.4.0-3
proxmox-backup-client: 3.2.7-1
proxmox-backup-file-restore: 3.2.7-1
proxmox-firewall: 0.5.0
proxmox-kernel-helper: 8.1.0
proxmox-mail-forward: 0.2.3
proxmox-mini-journalreader: 1.4.0
proxmox-offline-mirror-helper: 0.6.6
proxmox-widget-toolkit: 4.2.3
pve-cluster: 8.0.7
pve-container: 5.1.12
pve-docs: 8.2.3
pve-edk2-firmware: 4.2023.08-4
pve-esxi-import-tools: 0.7.1
pve-firewall: 5.0.7
pve-firmware: 3.13-1
pve-ha-manager: 4.0.5
pve-i18n: 3.2.2
pve-qemu-kvm: 9.0.2-2
pve-xtermjs: 5.3.0-3
qemu-server: 8.2.4
smartmontools: 7.3-pve1
spiceterm: 3.3.0
swtpm: 0.8.0+pve1
vncterm: 1.8.0
zfsutils-linux: 2.2.4-pve1

Running Home Assistant in the VM CPU usage at 3%

 

[fiona]

What physical CPU do you have? Does using CPU type host for the VM work around the issue?

 

[nivek1612]

Intel(R) Core(TM) i7-4510U CPU @ 2.00GHz

I will give the CPU type host a try later

EDIT: Sorry where would I change CPU type to host that can't see it

 

[fiona]

EDIT: Sorry where would I change CPU type to host that can't see it

In the VM's Hardware panel, select Processors, use the Edit button and select Type.

 

[nivek1612]

In the VM's Hardware panel, select Processors, use the Edit button and select Type.

Got it. Will need to do it later as the VM is active and busy and I will need to stop it to change the processor.

 

[nivek1612]

Changed CPU to host
Performed snapshot with RAM
VM was not responding and had to be restarted so the problem remains even with host CPU

 

[fiona]

Okay, thank you for testing! What does qm status <ID> --verbose show while the VM is unresponsive? Can you still ping it? See the display?