Summary Mem Usage Does Not Match OS Free

[hackerkatt]

Hello,

This is my first post and not sure I'm posting in the right place. I only see "Proxmox VE: Installation and configuration" and "Networking and Firewall".

I created a VM w/ 2GB of RAM. The VM Summary shows the VM memory is close to being maxed but the OS free -h says it's no where close. I have a minimal Ubuntu 20.04 Server w/ Docker install. I questioned the memory use because 1) a similar VM config shows what I would expect, 2) Similar VMs I've set up on ESXi haven't shown the same discrepancy. I understand that ubuntu server has a larger memory requirement. But I don't understand the diff between the VM Summay memory metric and what the OS reports. I Can someone shed some light on this? Thank you very much.

HK








Here's a similar configured VM using Debian 10 minimal

 

[hackerkatt]

I stumbled across this post https://www.reddit.com/r/Proxmox/comments/eth1ok/summary_is_memory_useage_bugged/ that made some good points. It also suggested that you install qemu-guest-agent then enable it on the VM guest options. I've done so and rebooted the VM. Memory Summary metrics looks more in line with what I would expect. I'll give it some time to verify. If continue to see the numbers in line with each other, I'll consider the matter closed.

 

[H4R0]

You have to calculate "used" + "buff/cache" because that's what the vm actually uses. And it's exactly what proxmox reports.

Disabling cache is not possible in linux, just don't over commit when using vm's.

https://www.linuxatemyram.com/