Can we tune memory ballooning to start higher then 80% host usage?

[Helmo]

On a Proxmox host I noticed that memory ballooning kicks in when the host is reaching 80% capacity on it's RAM. This was confirmed in the docs.

Is there a setting to tune that?

On a 128GB machine it feels not ok to take memory from a guest when the host still has 25GB free.

The 'free' space is used for caching of course ... but it seems a bit much.

 

[dcsapak]

Is there a setting to tune that?

not currently no, but feel free to file an enhancement request, no promises as to how/if/when it will be implemented though
https://bugzilla.proxmox.com/

 

[Helmo]

Any idea which component is setting this limit? A kernel module?

 

[dcsapak]

no the autoballooning is done by one of our daemons (pvestatd) and this limit is hardcoded at the moment

 

[Helmo]

Thanks... now requested in https://bugzilla.proxmox.com/show_bug.cgi?id=2413