On Mon, Jun 25, 2007 at 10:15:07AM +0100, Simon Riggs wrote: > On Mon, 2007-06-25 at 01:33 -0400, Greg Smith wrote: > > On Sun, 24 Jun 2007, Simon Riggs wrote: > > > > > Greg can't choose to use checkpoint_segments as the limit and then > > > complain about unbounded recovery time, because that was clearly a > > > conscious choice. > > > > I'm complaining > > I apologise for using that emotive phrase. > > > only because everyone seems content to wander in a > > direction where the multiplier on checkpoint_segments for how many > > segments are actually active at once will go up considerably, which can > > make a known problem (recovery time) worse. > > +50% more. Recovery time is a consideration that can be adjusted for. We > have done nothing to make recovery rate worse; the additional WAL leads > to an increased recovery time *only* if you keep the same parameter > settings. There is no reason to keep them the same, nor do we promise > that parameters will keep the exact meaning they had previous releases. > > As you say, we can put comments in the release notes to advise people of > 50% increase in recovery time if the parameters stay the same. That > would be balanced by the comment that checkpoints are now considerably > smoother than before and more frequent checkpoints are unlikely to be a > problem, so it is OK to reduce the parameters from the settings you used > in previous releases.
Didn't we already add other featuers that makes recovery much *faster* than before? In that case, are they faster enugh to neutralise this increased time (a guestimate, of course) Or did I mess that up with stuff we added for 8.2? :-) //Magnus ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq