Re: max_standby_delay considered harmful

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Stephen Frost <sfrost@snowman.net>
Cc: Stefan Kaltenbrunner <stefan@kaltenbrunner.cc>, Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgreSQL.org
Date: 2010-05-03T18:22:31Z
Lists: pgsql-hackers
On Mon, 2010-05-03 at 13:13 -0400, Stephen Frost wrote:
> * Simon Riggs (simon@2ndQuadrant.com) wrote:
> > I guarantee that if that proposal goes in, people will complain about
> > that also. Last minute behaviour changes are bad news. I don't object to
> > adding something, just don't take anything away. It's not like the code
> > for it is pages long or anything.
> 
> I have to disagree with this.  If it goes into 9.0 this way then we're
> signing up to support it for *years*.  With something as fragile as the
> existing setup (as outlined by Tom), that's probably not a good idea.
> We've not signed up to support the existing behaviour at all yet-
> alpha's aren't a guarentee of what we're going to release.

That's a great argument, either way. We will have to live with 9.0 for
many years and so that's why I mention having both. Make a choice either
way and we take a risk. Why?

> > The trade off is HA or queries and two modes make sense for user choice.
> 
> The option isn't being thrown out, it's just being made to depend on
> something which is alot easier to measure while still being very useful
> for the trade-off you're talking about.  I don't really see a downside
> to this, to be honest.  Perhaps you could speak to the specific user
> experience difference that you think there would be from this change?
> 
> +1 from me on Tom's proposal.

-- 
 Simon Riggs           www.2ndQuadrant.com