Re: pgsql: Reset master xmin when hot_standby_feedback disabled.

On 2014-05-28 23:39:56 +0100, Simon Riggs wrote:
> On 28 May 2014 23:36, Andres Freund <andres(at)2ndquadrant(dot)com> wrote:
>
> > On 2013-02-04 10:35:31 +0000, Simon Riggs wrote:
> >> Reset master xmin when hot_standby_feedback disabled.
> >> If walsender has xmin of standby then ensure we
> >> reset the value to 0 when we change from hot_standby_feedback=on
> >> to hot_standby_feedback=off.
> >
> > Unless somebody protests I'd like to backpatch this change to 9.2 and
> > 9.1. This imo is a bugfix, not a new feature. What currently happens <
> > 9.3 when hot_standby_feedback is disabled after being enabled is that
> > the walsender's xmin horizon doesn't increase until disconnected. That's
> > pretty hard to diagnose and can cause severe problems.
>
> Good thought. I'll backpatch.

Cool. Happy to escape my first backpatch for a little while longer :)!

Greetings,

Andres Freund

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Andres Freund http://www.2ndQuadrant.com/
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