Re: pgsql: Reset master xmin when hot_standby_feedback disabled.

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.

--
Simon Riggs http://www.2ndQuadrant.com/
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