How to set Swappiness permanent to 0 on Proxmox 9

[Ralf Wolbers]

On Proxmox 8,4 the following two Commands set swappiness permanent to 0:

sysctl -w vm.swappiness=0

echo "vm.swappiness=0" | tee -a /etc/sysctl.conf

The value stays 0 after Reboot. On Proxmox 9 it does not save it permanent. After Reboot it is 60 again

 

[leesteken]

/etc/sysctl.conf no longer exists on PVE 9.x. Put your lines in a file inside /etc/sysctl.d/ like /etc/sysctl.d/71-local.conf for example. This is not specific to Proxmox but a change in Debian 13/Trixie and later.

EDIT: The pve8to9 warns about this: https://forum.proxmox.com/threads/2-warnings-in-pve8to9-check.169351/

 

[Johannes S]

Why would you do this? There are good reasons for swap even on hosts with more than enough memory:
https://chrisdown.name/2018/01/02/in-defence-of-swap.html

You could use even part of your RAM as a cimpresses swap device reduing iotimes and giving more headram before memory runs out: https://pve.proxmox.com/wiki/Zram

See also: https://forum.proxmox.com/threads/recommended-amount-of-swap.171319/post-798247

 

[SInisterPisces]

Why would you do this? There are good reasons for swap even on hosts with more than enough memory:
https://chrisdown.name/2018/01/02/in-defence-of-swap.html

You could use even part of your RAM as a cimpresses swap device reduing iotimes and giving more headram before memory runs out: https://pve.proxmox.com/wiki/Zram

See also: https://forum.proxmox.com/threads/recommended-amount-of-swap.171319/post-798247

I've seen that same article, @Johannes S .

One of the reasons messing with swap at all is so frustrating is that's so dependenet on the individual build.

Proxmox's default ZFS-based install doesn't even create a swap at all:

 

[Johannes S]

Proxmox's default ZFS-based install doesn't even create a swap at all:

Yes because in some cases this might led to problems if the swap is on zfs see https://pve.proxmox.com/pve-docs/chapter-sysadmin.html#zfs_swap
Using a dedicated swap partition would work though or zramswap: https://pve.proxmox.com/wiki/Zram
And even with enough RAM and ZFS the argumens of Chris Downs should be taken into account.