Re: Keepalive for max_standby_delay

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Stephen Frost <sfrost@snowman.net>, Josh Berkus <josh@agliodbs.com>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, pgsql-hackers@postgresql.org
Date: 2010-06-02T18:03:50Z
Lists: pgsql-hackers
On Wed, 2010-06-02 at 13:45 -0400, Tom Lane wrote:
> Stephen Frost <sfrost@snowman.net> writes:
> > * Tom Lane (tgl@sss.pgh.pa.us) wrote:
> >> Comments?
> 
> > I'm not really a huge fan of adding another GUC, to be honest.  I'm more
> > inclined to say we treat 'max_archive_delay' as '0', and turn
> > max_streaming_delay into what you've described.  If we fall back so far
> > that we have to go back to reading WALs, then we need to hurry up and
> > catch-up and damn the torpedos.
> 
> If I thought that 0 were a generally acceptable value, I'd still be
> pushing the "simplify it to a boolean" agenda ;-).  The problem is that
> that will sometimes kill standby queries even when they are quite short
> and doing nothing objectionable.

OK, now I understand. I was just thinking the same as Stephen, but now I
agree we need a second parameter.

-- 
 Simon Riggs           www.2ndQuadrant.com