Re: could not create directory "...": File exists

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Stephen Frost <sfrost@snowman.net>
Cc: pgsql-hackers@postgresql.org
Date: 2013-01-18T00:26:18Z
Lists: pgsql-hackers
Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> This seems to provide a reasonably principled
>> argument why we might want to fix this case with a localized use of an
>> MVCC scan before we have such a fix globally.

> I had discussed that idea a bit with Andres on IRC and my only concern
> was if there's some reason that acquiring a snapshot during createdb()
> would be problematic.  It doesn't appear to currently and I wasn't sure
> if there'd be any issues.

Don't see what.  The main reason we've not yet attempted a global fix is
that the most straightforward way (take a new snapshot each time we
start a new SnapshotNow scan) seems too expensive.  But CREATE DATABASE
is so expensive that the cost of an extra snapshot there ain't gonna
matter.

			regards, tom lane