[linux-lvm] Snapshot behavior on classic LVM vs ThinLVM

[Xen]

Zdenek Kabelac schreef op 13-04-2017 16:33:

> Hello
> 
> Just let's repeat.
> 
> Full thin-pool is NOT in any way comparable to full filesystem.
> 
> Full filesystem has ALWAYS room for its metadata - it's not pretending
> it's bigger - it has 'finite' space and expect this space to just BE
> there.
> 
> Now when you have thin-pool - it cause quite a lot of trouble across
> number of layers.  There are solvable and being fixed.
> 
> But as the rule #1 still applies - do not run your thin-pool out of
> space - it will not always heal easily without losing date - there is
> not a simple straighforward way how to fix it (especially when user
> cannot ADD any new space he promised to have)
> 
> So monitoring pool and taking action ahead in time is always superior
> solution to any later  postmortem systems restores.

Yes that's what I said. If your thin pool runs out, your system will 
crash.

Thanks for alluding that this will also happen if a thin snapshot causes 
this (obviously).

Regards.