Re: [HACKERS] postmaster locking issues.

On Sat, 10 Oct 1998, Bruce Momjian wrote:

> > After looking into the issue of using PID file locks vs. flock/unlock, I have
> > come to the following conclusions:
> >
> > 1. It is generally agreed that a PID lock file should replace the current me-
> > thod of locking (fcntl based locking). (See the message thread with
> > '[HACKERS] flock patch breaks things here' in the subject).
> >
> > 2. The purpose of the lock file is to prevent multiple postmasters from run-
> > ning on the same port and database.
> >
> > 3. Two PID files will be necessary, one to prevent mulitple instances of post-
> > masters from running against the same data base, and one to prevent
> > multiple
> > instances from using the same port.
> >
> > 4. The database lock will be located in the DATA directory being locked.
> >
> > 5. The port lock will be kept in '/var/opt/pgsql/lock/'.
>
> Yes, except lock file should be kept in /tmp. I don't have
> /var/opt/..., and I doubt others do either.

My RedHat system doesn't have /var/opt either. I'd agree with /tmp as
that's been in every unix style system I've used so far.

--
Peter T Mount peter(at)retep(dot)org(dot)uk
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