Re: Hot Standby remaining issues

Kevin Grittner <kevin.grittner@wicourts.gov>

From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Simon Riggs" <simon@2ndQuadrant.com>, "Heikki Linnakangas" <heikki.linnakangas@enterprisedb.com>
Cc: "PostgreSQL-development" <pgsql-hackers@postgresql.org>
Date: 2009-12-04T15:29:21Z
Lists: pgsql-hackers
Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> wrote:
 
> If the system is completely idle, and no WAL is written, we skip
> xlog switches too, even if archive_timeout is set . It would be
> pointless to create a stream of WAL files with no content except
> for the XLOG_SWITCH records.
 
It's not pointless if you want to monitor that your backup system is
healthy.  This was previously mentioned a couple years ago:
 
http://archives.postgresql.org/pgsql-general/2007-10/msg01448.php
 
It turns out that it's been working fine under 8.3.  Of course, we
can always add a crontab job to do some small bogus update to force
WAL switches, so it's not the end of the world if we lose the 8.3
behavior; but my preference would be that if a WAL switch interval
is specified, the WAL files switch at least that often.
 
-Kevin