Re: max_standby_delay considered harmful

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgreSQL.org
Date: 2010-05-05T20:52:26Z
Lists: pgsql-hackers
On Wed, 2010-05-05 at 16:58 +0300, Heikki Linnakangas wrote:
> Let's have a setting similar to
> statement_timeout, that specifies how long a statement is allowed to
> run until it becomes subject to killing if it conflicts with recovery
> (actually, it would have to be a per-transaction setting, at least in
> serializable mode). This would be similar to Tom's proposal, and it
> would have the same drawback that it would give no guarantee on how
> much the standby can fall behind. However, it would be easier to
> understand:
> a query gets to run for X seconds, and after that it will be killed if
> it gets in the way.

If you want this, I have no problem with you getting this (though new feature
alert sirens going off, presumably).

I only have a problem with the suggestion that this replaces the current
max_standby_delay. There is no good case for only a single option.

-- 
 Simon Riggs           www.2ndQuadrant.com