Re: New sync commit mode remote_write

On Tue, Apr 24, 2012 at 12:21 PM, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:
> On Thu, Apr 19, 2012 at 11:50 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On 4/19/12, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:
>>> The work around would be for the master to refuse to automatically
>>> restart after a crash, insisting on a fail-over instead (or a manual
>>> forcing of recovery)?
>>
>> I suppose that would work, but I think Simon's idea is better: don't
>> let the slave replay the WAL until either (a) it's promoted or (b) the
>> master finishes the fsync.   That boils down to adding some more
>> handshaking to the replication protocol, I think.
>
> Alternative c) is that the master automatically recovers from a crash,
> but doesn't replay that particular wal record because it doesn't find
> it on disk, so the slave has to be instructed to throw it away.

Right. Which kind of stinks.

> (Or
> perhaps the slave could feed the wal back to the master, so the master
> could replay it?)

Yes, that would be a very nice enhancement, I think.

--
Robert Haas
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