Re: pg_ctl non-idempotent behavior change

Tom Lane wrote:
> Jeff Janes <jeff(dot)janes(at)gmail(dot)com> writes:
> > After 87306184580c9c49717, if the postmaster dies without cleaning up (i.e.
> > power outage), running "pg_ctl start" just gives this message and then
> > exits:
>
> > pg_ctl: another server might be running
>
> > Under the old behavior, it would try to start the server anyway, and
> > succeed, then go through recovery and give you back a functional system.
>
> > From reading the archive, I can't really tell if this change in behavior
> > was intentional.
>
> Hmm. I rather thought we had agreed not to change the default behavior,
> but the commit message fairly clearly says that the default behavior is
> being changed. This case shows that that change was inadequately
> thought through.
>
> > Anyway it seems like a bad thing to me. Now the user has a system that
> > will not start up, and is given no clue that they need to remove
> > "postmaster.pid" and try again.
>
> Yeah, this is not tolerable. We could think about improving the logic
> to have a stronger check on whether the old server is really there or
> not (ie it should be doing something more like pg_ping and less like
> just checking if the pidfile is there). But given how close we are to
> beta, maybe the best thing is to revert that change for now and put it
> back on the to-think-about-for-9.4 list. Peter?

Are we going to unrevert this patch for 9.5?

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