Re: Sync Rep for 2011CF1

On Fri, 2011-01-21 at 14:34 +0100, Magnus Hagander wrote:
> On Fri, Jan 21, 2011 at 14:24, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > On Fri, 2011-01-21 at 14:45 +0200, Heikki Linnakangas wrote:
> >> * it seems like overkill to not let clients to even connect when
> >> allow_standalone_primary=off and no synchronous standbys are available.
> >> What if you just want to run a read-only query?
> >
> > That's what Aidan requested, I agreed and so its there. You're using
> > sync rep because of writes, so you have a read-write app. If you allow
> > connections then half of the app will work, half will not. Half-working
> > isn't very useful, as Aidan eloquently explained. If your app is all
> > read-only you wouldn't be using sync rep anyway. That's the argument,
> > but I've not got especially strong feelings it has to be this way.
> >
> > Perhaps discuss that on a separate thread? See what everyone thinks?
>
> I'll respond here once, and we'll see if more people want to comment
> then we can move it :-)
>
> Doesn't this make a pretty strange assumption - namely that you have a
> single application? We support multiple databases, and multiple users,
> and multiple pretty much anything - in most cases, people deploy
> multiple apps. (They may well be part of the same "solution" or
> whatever you want to call it, but parts may well be readonly - like a
> reporting app, or even just a monitoring client)

There are various problems whatever we do. If we don't like one way, we
must balance that by judging what happens if we do things the other way.

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