Re: Streaming replication status

On Tue, 2010-01-12 at 08:24 +0100, Stefan Kaltenbrunner wrote:
> Fujii Masao wrote:
> > On Tue, Jan 12, 2010 at 1:21 PM, Greg Smith <greg(at)2ndquadrant(dot)com> wrote:
> >> I don't think anybody can deploy this feature without at least some very
> >> basic monitoring here. I like the basic proposal you made back in September
> >> for adding a pg_standbys_xlog_location to replace what you have to get from
> >> ps right now:
> >> http://archives.postgresql.org/pgsql-hackers/2009-09/msg00889.php
> >>
> >> That's basic, but enough that people could get by for a V1.
> >
> > Yeah, I have no objection to add such simple capability which monitors
> > the lag into the first release. But I guess that, in addition to that,
> > Simon wanted the capability to collect the statistical information about
> > replication activity (e.g., a transfer time, a write time, replay time).
> > So I'd like to postpone it.
>
> yeah getting that would all be nice and handy but we have to remember
> that this is really our first cut at integrated replication. Being able
> to monitor lag is what is needed as a minimum, more advanced stuff can
> and will emerge once we get some actual feedback from the field.

Though there won't be any feedback from the field because there won't be
any numbers to discuss. Just "it appears to be working". Then we will go
into production and the problems will begin to be reported. We will be
able to do nothing to resolve them because we won't know how many people
are affected.

--
Simon Riggs www.2ndQuadrant.com