Andrew Dunstan <andrew@dunslane.net> writes:
> Tom Lane wrote:
>> That can only be a solution if postmaster child processes will inherit
>> the lock.
> I don't think so, no. But we could have the children explicitly acquire
> a shared lock, so if the postmaster at startup tried to grab an
> exclusive lock that would fail if any child were still alive.
We've been through this before. That is not an acceptable substitute
because there's a race condition: a new child might have been launched
but not yet acquired the lock. We need the lock to actually be
inherited across the fork/exec so there is no window where it's not held.
regards, tom lane