Re: tracking commit timestamps

On 2014-11-11 16:10:47 +0000, Simon Riggs wrote:
> On 4 November 2014 08:23, Andres Freund <andres(at)2ndquadrant(dot)com> wrote:
>
> >> 6) Shouldn't any value update of track_commit_timestamp be tracked in
> >> XLogReportParameters? That's thinking about making the commit timestamp
> >> available on standbys as well..
> >
> > Yes, it should.
>
> Agree committs should be able to run on standby, but it seems possible
> to do that without it running on the master.

I don't think that's realistic. It requires WAL to be written in some
cases, so that's not going to work. I also don't think it's a
particularly interesting ability?

> The two should be unconnected.

Why?

> Not sure why we'd want to have parameter changes on master reported?

So it works correctly. We're currently truncating the slru on startup
when the guc is disabled which would cause problems WAL records coming
in from the primary. I think the code also needs some TLC to correctly
work after a failover.

Greetings,

Andres Freund

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