Re: Fix for erroneous warning on Shutdown

On Fri, 2004-06-11 at 19:25, Tom Lane wrote:
> Simon Riggs <simon(at)2ndquadrant(dot)com> writes:
> > Minor patch to correct erroneous warning in cvs tip, believed to be a
> > very minor regression.
>
> This patch is wrong; it effectively disables the warning altogether.
>
> > When a shutdown was requested within CHECKPOINT_SECONDS of a checkpoint,
> > the shutdown code in the bgwriter (which has does checkpointing) would
> > issue the erroneous message:
>
> I don't think so ... the shutdown path doesn't go through this code.
> Could you take another look at the cause of what you saw?

Hmmm...perhaps I should submit this as a *low priority* bug then, rather
than just a patch?

As of now, (i.e. even including the new bgwriter shutdown) if you:
1. start postmaster
2. do some work that writes xlog
3. shutdown within some few seconds of startup

you get a WARNING suggesting you increase CHECKPOINT_SEGMENTS, which is
clearly erroneous since no checkpoint has taken place since startup.

Not exactly a common circumstance, I grant you, but it does seem to be a
regression nonetheless. My thinking was that the circumstance was not
limited to this edge case, but actually any shutdown within 30s of a
checkpoint, but the latter is just speculation.

Only reason I spotted it is I've been doing a lot of startup/shutdown
work recently...

Best Regards, Simon Riggs