Re: [PATCH] Clear FatalError earlier during crash restart

On Wed, Sep 30, 2026 at 05:44:16AM +0530, Ayush Tiwari wrote:
> I think that argues for the smaller fix, at least on the back branches.
> I'd tried the diff below[1] before clearing FatalError: it SIGQUITs the new
> children on smart/fast shutdown, without changing the crash-restart
> behavior. It fixed my repro on 46024c573bc, though it logs an abnormal
> shutdown.

Yeah, I can see that, due to this part I think because the FatalError
flag would be set? Quoting the relevant part from postmaster.c:
if (Shutdown > NoShutdown && pmState == PM_NO_CHILDREN)
{
if (FatalError)
{
ereport(LOG, (errmsg("abnormal database system shutdown")));
ExitPostmaster(1);
}
else
{
/*
* Normal exit from the postmaster is here. We don't need to log
* anything here, since the UnlinkLockFiles proc_exit callback
* will do so, and that should be the last user-visible action.
*/
ExitPostmaster(0);
}
}

So that just feels, err, okay-ish, because the logs reflect what we
are actually doing?

So plugging in an extra HandleFatalError() while the pmState is
PM_STOP_BACKENDS feels like a good compromise, on top of my mind. It
would mean that your too-early-shutdown request on crash recovery
would still persist on v17 and older branches, but at least the
checkpointer and the I/O workers would be able to understand that they
need to stop, and the SIGQUIT sent would be promoted to a SIGKILL
after the AbortStartTime timeout is armed.

I was slightly on the edge about your TAP test and its fancy restore
command, but I don't want to leave that untested, either, as that
seems like the same thing as Justin's case. Perhaps only do that on
HEAD first, let it brew for a bit, and consider it down later on if
really necessary? These shutdown changes stress me quite a bit when
it comes to a backpatch, because they can be nasty very easily with
one mistake, and I like a peaceful sleep. On top of that v19 is close
by.
--
Michael