Re: [PATCH] doc: clarify pg_stat_lock.fastpath_exceeded scope

Hi Bertrand-san,

Thanks for the review.

> Should we add a description of the consequences of not being able to
> acquire the lock in fast-path (when there are no available slots)?
> For example, we could say that this is considerably more expensive
> and may be subject to contention.

Agreed.  v3 adds the following paragraph at the end of the Fast-Path
Locking subsection:

+     <para>
+      Acquiring a lock via the main lock table is considerably more
+      expensive than the fast path, and under heavy concurrent lock
+      activity can become a point of contention (observable as the
+      <literal>LockManager</literal> wait event).
+     </para>

Other parts of the patch are unchanged from v2.
v3 attached.

Regards,
Tatsuya Kawata