Re: leaking lots of unreferenced inodes (pg_xlog files?), maybe after moving tables and indexes to tablespace on different volume

On Mar 13, 2013 3:04 AM, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> Palle Girgensohn <girgen(at)FreeBSD(dot)org> writes:
> > ... I got lots of space freed
> > up, but it seems that after that the disk usage grows linearly (it seems
> > to leave many inodes unreferenced).
>
> Hm. We've seen issues in the past with PG processes failing to close
> no-longer-useful files promptly, but ...
>
> > Strange thing is I cannot find any open files.
>
> ... that suggests there's something else going on.
>
> > The unreferenced inodes are almost exclusively around 16 MB in size, so
> > i.e. they would most probably all be pg_xlog files.
>
> Have you got any sort of WAL archiving active, and if so maybe that's
> holding onto WAL files? Not that it's clear how come lsof wouldn't
> tattle on an archiving process either.
>
> > Stopping postgresql briefly did not help, I tried that.
>
> That seems to point the finger at some non-postgres cause. I confess
> I can't guess what.
>

Yeah, unreferenced inodes with no open files, and only discoverable with
fsck sounds like a filsystem bug to me. Particularly since it showed up
just after a operating system upgrade, and doesn't go away with a postgres
restart...

/Magnus