[pve-devel] [PATCH] ZFS ARC size not taken into account by pvestatd or ksmtuned

[Stephane CHAZELAS]

2021-01-23 04:14:52 -0500, Bruce Wainer:
[...]
> Alternatively if you are not willing to go through the steps of submitting
> this yourself, we might be able to work things out so I can submit it.
[...]

Hi Bruce,

yes please. That's a very simple change. The idea is just to
count the ARC size as buffer/cache like the rest of the buffer/
cache. It doesn't really matter much how it's done exactly. I
use git rarely enough that it always me hours to get back into
it.

I see that ksmtuned is actually upstream at RedHat so I suppose
Proxmox will likely want to add the change as an extra debian
patch.

I think I should point out that I've not revisited that issue in
years. And at the time the aim was to quickly address the issue
for our specific use case. There may be better ways to address
it these days. In particular, I'm not sure why the kernel
doesn't account the ARC in buffers/cache in the first place,
maybe that's customisable now. I've not had a look at that
/proc/pressure thing referenced in the latest commit of
ProcFSTools either. But in any case, the patch I submitted has
proved to be an improvement for us.

Cheers,
Stephane