Re: pg_ctl start may return 0 even if the postmaster has been already started on Windows

At Thu, 06 Jun 2024 17:15:15 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in 
> At Thu, 06 Jun 2024 16:45:00 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in 
> > I have been thinking about this since then. At first, I thought it
> > referred to FindFirstChangeNotification() and friends, and inotify on
> > Linux. However, I haven't found a way to simplify the specified code
> > area using those APIs.
> 
> By the way, the need to shift by 2 seconds to tolerate clock skew
> suggests that the current launcher-postmaster association mechanism is
> somewhat unreliable. Couldn't we add a command line option to
> postmaster to explicitly pass a unique identifier (say, pid itself) of
> the launcher? If it is not specified, the number should be the PID of
> the immediate parent process.

No. The combination of pg_ctl's pid and timestamp, to avoid false
matching during reboot.

> This change avoids the need for the special treatment for Windows.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center