Re: Speedup twophase transactions

On 12 January 2016 at 06:41, Michael Paquier <michael(dot)paquier(at)gmail(dot)com>
wrote:

>
> + if (log_checkpoints && n > 0)
> + ereport(LOG,
> + (errmsg("%u two-phase state files were
> written "
> + "for long-running
> prepared transactions",
> + n)));
> This would be better as an independent change. That looks useful for
> debugging, and I guess that's why you added it.
>

The typical case is that no LOG message would be written at all, since that
only happens minutes after a prepared transaction is created and then not
terminated. Restarting a transaction manager likely won't take that long,
so it implies a crash or emergency shutdown of the transaction manager.

I think it is sensible and useful to be notified of this as a condition the
operator would wish to know about. The message doesn't recur every
checkpoint, it occurs only once at the point the files are created, so its
not log spam either.

--
Simon Riggs http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
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