Re: Do we need to handle orphaned prepared transactions in the server?

On Tue, Apr 21, 2020 at 01:52:46PM +0900, Michael Paquier wrote:
> On Mon, Apr 20, 2020 at 10:35:15PM -0400, Bruce Momjian wrote:
> > On Thu, Apr 16, 2020 at 03:11:51PM -0400, Tom Lane wrote:
> >> If we were going to go down the path of periodically logging warnings
> >> about old prepared transactions, some single-instance background task
> >> like the checkpointer would be a better place to do the work in. But
> >> I'm not really recommending that, because I agree with Robert that
> >> we just plain don't want this functionality.
> >
> > I thought we would just emit a warning at boot time.
>
> That's more tricky than boot time (did you mean postmaster context?),
> especially if you are starting a cluster from a base backup as you
> have no guarantee that the 2PC information is consistent by just
> looking at what's on disk (some of the 2PC files may still be in WAL
> records to-be-replayed), so a natural candidate to gather the
> information wanted here would be RecoverPreparedTransactions() for a
> primary, and StandbyRecoverPreparedTransactions() for a standby.

Sorry, I meant something in the Postgres logs at postmaster start.

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Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EnterpriseDB https://enterprisedb.com

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