On 08/30/2016 06:12 PM, Michael Paquier wrote:
> Really? Here are the doc quotes that I guess matter, and I read that
> differently than you do:
> If any of the current synchronous standbys disconnects for whatever
> reason, it will be replaced immediately with the next-highest-priority
> standby.
> [...]
> For example, a setting of 3 (s1, s2, s3, s4) makes transaction commits
> wait until their WAL records are received by *three higher-priority
> standbys* chosen from standby servers s1, s2, s3 and s4.
>
> This clearly says that we wait for the servers that have a higher
> priority, meaning that we do *not* wait for any k elements in a set of
> n listed, but suggest that the order of the element matters.
Yeah, the problem is that "higher priority" isn't defined, and could
mean a lot of things. It *is* defined in the actual section on
synchronous standby, though (25.2.8.2.); maybe what we need is less docs
under the GUC and more references to that?
Otherwise, you're going to have lots of people confused that it's
actually quorum commit, as witnessed by the current discussion. Right
now what's in the GUC doc page appears to be complete but isn't.
--
--
Josh Berkus
Red Hat OSAS
(any opinions are my own)