Re: Missed check for too-many-children in bgworker spawning

On 2019-Nov-04, Robert Haas wrote:

> On Mon, Nov 4, 2019 at 10:42 AM Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
> > > True, it's not a situation you especially want to be in.  However,
> > > I've lost count of the number of times that I've heard someone talk
> > > about how their system was overstressed to the point that everything
> > > else was failing, but Postgres kept chugging along.  That's a good
> > > reputation to have and we shouldn't just walk away from it.
> >
> > I agree with this point in principle.  Everything else (queries,
> > checkpointing) can fail, but it's critical that postmaster continues to
> > run [...]
> 
> Sure, I'm not arguing that the postmaster should blow up and die.

I must have misinterpreted you, then.  But then I also misinterpreted
Tom, because I thought it was this stability problem that was "utter
bunkum".

> I was, however, arguing that if the postmaster fails to launch workers
> for a parallel query due to process table exhaustion, it's OK for
> *that query* to error out.

That position makes sense to me.  It would be nice [..ponies..] for the
query to run regardless, but if it doesn't, it's not such a big deal;
the query could have equally failed to run in a single process anyway.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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