Re: [PATCH] A crash and subsequent recovery of themaster can cause the slave to get out-of-sync

Tom Lane wrote:
> [ back to dealing with this patch, finally ]
>
> "Florian G. Pflug" <fgp(at)phlo(dot)org> writes:
>> While creating the patch, I've been thinking if it might be worthwile
>> to note that we just did recovery in the ShutdownCheckpoint
>> (or create a new checkpoint type RecoveryCheckpoint). This wouldl allow
>> for more error checking, because then the slave could check that
>> safe_restartpoint() is true for all ShutdownCheckpoints that were not
>> after recovering.
>
> I concur that this is a good idea --- we should have a third checkpoint
> record type that shows that a crash recovery occurred. However, we can
> probably only do that for 8.3 and beyond. If we try to do it in
> existing release branches then there's likelihood of trouble due to WAL
> incompatibility between master and standby. While we do advise people
> to update their standbys first, I don't think it's worth risking such
> problems just to add some more error checking.
>
> Conclusion: we should apply Florian's patch as-is in 8.2, do something
> morally equivalent in 8.1 and before, and invent a
> CrashRecoveryCheckpoint record type in HEAD.

Sounds good.

Do you want me to code up such patches for 8.1 and 8.3 in the next days,
or is someone else already working on it?

greetings, Florian Pflug