Monitoring memory usage using ZFS

Blinkiz

Active Member
Jan 23, 2010
32
1
28
Stockholm Sweden
Hi
Am trying out Proxmox+ZFS on the same machine. Am new to ZFS.
Am monitoring my server with Zabbix and my memory usage is 90%. It is of course mostly ZFS cache but how do I monitor when am running out of memory? Will ZFS always be at 90% so I can set my alarms at 95%?
How do you guys monitor RAM usage when running virtual machines and ZFS on the same machine? How can I get insight into how much memory is my virtual machines using and how much is ZFS using? Proxmox WebGUI only shows total RAM usage without any insight on what is using the memory. Kinda bad because proxmox promotes ZFS so the WebGUI should in my opinion show better statistics around RAM usage in the summary page.
 

Dunuin

Famous Member
Jun 30, 2020
9,040
2,321
156
Germany
By default ZFS will use up to 50% of your RAM for caching. Look at memory "available" and not at memory "free". On your host you can check it with "free -h" and zabbix is collecting it as "Available memory" and "Available memory in %". Its no problem if "free" memory is down nearly 0% but "available" memory should always be a bit available (20% or so).
 
Last edited:
  • Like
Reactions: Ansy

Ansy

Active Member
Dec 20, 2018
44
7
28
51
The same issue with NetData https://www.netdata.cloud/ monitoring alarms.
IMHO it's better to switch it off. RAM must to work hard. ZFS is using RAM for the good things.
@Dunuin thanks for advice, I'll try to monitor available memory.
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get your own in 60 seconds.

Buy now!