Ram useage

[Riddleuk]

Morning
This should hopefully be my last question on pm7 as the forums has been great. I actually can get stuff to work well ready for presenting it to managers tomorrow as our way forward.

I managed to set up
Pfsense - min 2gb max 4gb
Open media vault - min 1gb max 4gb they have just moved to bullseye as well.
Plex - min 2gb max 4gb ( it's to make it easy to do client views of the work done as it's all video editing as all the servers are available from 1 account )

In the webgui it shows it's using 21gb of ram but if I look in htop it shows 13gb of ram. So I am a bit confused on what the ram useage actually is.

I was hoping to put a lemp stack in with 8gb of ram for a multi site webserver which based on 4x4x4 already in use should be fine but I am a bit worried it will go over the 32gb of ram if I add a 8gb VM to the stack.

If I reboot it shows the same ram useage as htop but wanted to be sure before I pop in the last one.

I am totally sold on Debian I never thought I would be. I used to be Ubuntu and mint all the way.

 

[dcsapak]

htop does not include the caches+buffer afair
better to use 'free -h' there you can see all relevant values

do you use zfs ? that takes up to 50% of the memory by default, but you can limit that https://pve.proxmox.com/wiki/ZFS_on_Linux#sysadmin_zfs_limit_memory_usage

 

[Riddleuk]

Thanks for the reply. I have indeed used zfs to make mirrors of SSD for VM is storage.

I will take a look at how to limit it.

 

[vshaev]

htop does not include the caches+buffer afair
better to use 'free -h' there you can see all relevant values

This is not the first time I have seen such an answer. And can anyone explain why the container displays the memory usage taking into account the buffer, but not in the node itself?
Isn't it logical to make them at least the same if you really want to take into account the buffer? Or am I not understanding something?

 

[dcsapak]

from the host point of view the container is using that, even if only with buff/cache. i am not sure if it would be easy to get that information, but it's probably a limit of cgroup memory handling