Re: "could not open relation with OID" errors after promoting the standby to master

On 24.05.2012 18:16, Robert Haas wrote:
> On Thu, May 24, 2012 at 10:13 AM, Joachim Wieland<joe(at)mcknight(dot)de> wrote:
>> I wouldn't have assumed any corruption was possible given that I did
>> clean shutdowns on both sides...
>
> The thing that's worrying me is that there's not really any such thing
> as a "clean" shutdown on a standby. When you shut down the master, it
> checkpoints. When you shut down the standby, it can't checkpoint, so
> I think it's still going to enter recovery at startup. It'd be
> interesting to know where that recovery began and ended as compared
> with the minimum recovery point just before the shutdown.

Perhaps we should introduce the concept of a clean standby shutdown. We
can't write a checkpoint record, but we could write the same information
somewhere else. Like in the control file. At startup, we'd see that we
did a clean shutdown at WAL point X/X, and start up without having to
read through all the WAL from the last master checkpoint.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com