Re: Deleted WAL files held open by backends in Linux

"Kevin Grittner" <Kevin.Grittner@wicourts.gov> writes:
> Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Determining whether it's still the current append target is not so
>> cheap though; it would require examining shared-memory status
>> which means taking a lock on that status (and it's a high-traffic
>> lock already).
> I haven't reviewed the internal locking techniques, so this may well
> be a dumb question, but...  Since we only care whether the value is
> equal, and an occasional false report of equality wouldn't hurt
> anything, couldn't we bypass the lock in this particular case?

Perhaps, if you didn't mind sometimes getting a wrong answer.
I guess the cost of that would be pretty small in this particular
usage.
        regards, tom lane