On Tue, Dec 18, 2012 at 7:03 PM, Josh Berkus <josh@agliodbs.com> wrote:
> 2. should we warn the user, or refuse to start up?
One nice property of allowing cyclicity is that it's easier to
syndicate application of WAL to a series of standbys before promotion
of exactly one to act as a primary (basically, to perform catch-up).
One could imagine someone wanting a configuration that was like:
+------------>r2| |
r1 <-----------+
This is only one step before:
r1------------>r2
or
r2------------>r1
(and, most importantly, after the cycle quiesces one can choose either one)
For my use, I'm not convinced that such checks and warnings are useful
if delivered by default, and I think outright rejection of cyclicity
is harmful.
--
fdr
