[SOLVED] Windows VM crashes another VM

[megusta]

Hallo,

i've problem if I start windows 8.1 VM, my openmediavault VM immediately crashes, a third VM with Fedora keep working. A while ago I had not this curiosity (I rarely use windows). If I start OMV again with windows, it works for some hours and crashes again. There is no problem with Fedora, I can start/ stop, all works fine.
I've no idea where to search? Is it proxmox or vm failure?

 

[apoc]

Is it possible your host runs out of memory?
When under pressure OSes start killing processes to prevent themselves crashing. That could be a KVM process of your VM.

 

[megusta]

Great, that was easy, thank you!
I've been experimenting and forgot to adjust the memory...

 

[apoc]

Glad that was it and I could help.
All the best

 

[megusta]

Sadly it solved only one problem, after some hours omv crashes again.
I've 16 GB on host, 8 GB for OMV and 4 GB for Fedora. So 4 GB for host must be enough (if I run Windows, I shutdown Fedora).
What can I check also?

 

[apoc]

Are you using ZFS?

 

[megusta]

Are you using ZFS?

yes, and I use auto-snapshot script...

 

[apoc]

Have you limited your RAM usage?
By default ZFS uses up to 50% memory for caching etc., which can be quite a lot. Especially when you don't have a lot of it (and I consider 16GB as "not a lot")

 

[megusta]

No, I've defaults settings. What would be best settings for me?

 

[apoc]

That is a damn good question.
I'd start with 1gb and then monitor ARC usage.
Point is. If you assign 8+4 GB memory for your VMS, they will consume potentially more as the host has to manage that. So your math (4gb left) is likely incorrect.

I think you can easily find threads here in the forum via "limit arc usage" and "monitor arc usage". Don't know this from the top of my head and writing from mobile

 

[megusta]

ok, thanks again