Re: DRAFT 9.6 release
Josh Berkus <[email protected]>
| Newsgroups | gmane.comp.db.postgresql.advocacy |
|---|---|
| Message-ID | <[email protected]> |
On 08/30/2016 06:32 PM, Amit Langote wrote: > On 2016/08/31 10:25, Josh Berkus wrote: >> On 08/30/2016 06:20 PM, Josh Berkus wrote: >>> 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. >> >> Also, if I do this: >> >> >> 2 ( g1, g2, g3 ) >> >> ... and g1, g2 and g3 are *groups* of three standbys each, what happens? >> Does it wait for one or more responses from g1 and from g2, or does >> getting two responses from g1 trigger a commit? > > We do not support specifying groups either. Names refer to the actual > standby names. Groups part of the earlier proposal(s) was taken out of > the patch, IIRC. ??? It's always been possible for me to give multiple standbys the same name, making a de-facto group. -- -- Josh Berkus Red Hat OSAS (any opinions are my own) -- Sent via pgsql-advocacy mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-advocacy