Re: pg_subtrans

Kevin Johnson <Kevin.Johnson@noaa.gov> writes:
> I am attempting to get information on the pg_subtrans directory.  I
> found this morning that one had a large number of files queued in it.
> It filled the disk partition on which pgdata resides.  After moving,
> linking and restarting as a temporary solution, the engine properly
> worked off these files.  So, I'm trying now to get to the root cause of
> why it filled in the first place -- however I'm not sure when postgres
> engine uses this directory.  I've searched the documentation and mailing
> list archive, but can't find much.  Can anyone give me a link or some
> more information?

I don't recall the exact horizon for pg_subtrans offhand, but I'm pretty
sure that it's determined by your oldest open transaction.  Look around
for idle-in-transaction sessions.

            regards, tom lane