Re: Re: [COMMITTERS] pgsql: Start background writer during archive recovery.

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> Tom Lane wrote:
>> The thing wrong with it is assuming that nothing interesting will happen
>> during proc_exit().  We hang enough stuff on on_proc_exit hooks that
>> that seems like a pretty shaky assumption.

> I can't get too worried, given that proc_exit() is a very well-beaten 
> code path. Admittedly not so much for an auxiliary process, but that's 
> just a dumbed down version of what happens with a full-blown backend.

Well, you're assuming that no future patch or add-on module will put
anything into an on_proc_exit hook that might interact with other
processes.  It might be fine now but I don't think it's very robust.

> However I started looking into that idea anyway, and figured that it 
> does simplify the logic in postmaster.c quite a bit, so I think it's 
> worth doing on those grounds alone.

Couldn't you get rid of PMSIGNAL_RECOVERY_COMPLETED altogether?  If the
startup process exits with code 0, recovery is complete, else there
was trouble.  I find this SetPostmasterSignal bit quite ugly anyway.
        regards, tom lane