Andres Freund <andres@anarazel.de> writes:
> It'd be quite possible to address the race-condition by moving the
> updating of the control file to postmaster, to the
> CheckPostmasterSignal(PMSIGNAL_BEGIN_HOT_STANDBY) block. That'd require
> updating the control file from postmaster, which'd be somewhat ugly.
No, I don't like that at all. Has race conditions against updates
coming from the startup process.
> Perhaps that indicates that field shouldn't be in pg_control, but in the
> pid file?
Yeah, that would be a different way to go at it. The postmaster would
probably just write the state of the hot_standby GUC to the file, and
pg_ctl would have to infer things from there.
regards, tom lane
