Comment # 24 on bug 967152 from Richard Brown

(In reply to ill lume from comment #23)
> "The recommended root partition size for an openSUSE btrfs root filesystem
> is *at least* 40GB"
> 
> I didn't know that. It is not in the documentation I read about 13.2 or in
> the info that displays as the machine is installing.
>  Is there no way for the installer to warn the user that at install time if
> it is too small? It already tells you about missing swap partition,
> subvolume stuff, etc.

On Leap, Tumbleweed, and SLE 12, YaST will automatically disable shapshots if
space is too low and warn you if you try to enable them again

That said, the problem is not trivial - a minimal installation that rarely
changes probably only requires an 8GB root partition for snapshots

And YaST doesn't know what you're installing until after you've decided about
the partitions, so it's really down to the user to make sure they provide
sufficient space for their use case

> "
> If you're an exceptionally heavy user, making lots of changes to your
> packages, then you either need more,"
> 
> I update that machine like once a month, if that.

I find your problems hard to believe then - While running Tumbleweed (which has
a much larger pace of change) on a system with a 32GB root partition (too small
for weekly updates of Tumbleweed IMHO) it takes over 2 months of weekly updates
before I ran out of space caused by snapshots

> 
> "or you need to adjust your snapper configuration accordingly to clean up
> based on your environment."
> 
> Is it possible to set snapper to not keep so many snapshots if the free
> space on the drive falls below a certain amount? Or for zypper to check if
> there is enough space available before it starts an upgrade? It already
> knows how much will be used doesn't it?

No, and you wouldn't want either . It's important snapper captures all the
changes it can in order to be a rollback service you can rely on.