Merge pull request #64114 from zdover23/wip-doc-2025-06-23-backport-64103-to-reef

reef: doc/radosgw: improve "pubsub_push_pending" info

Reviewed-by: Anthony D'Atri <anthony.datri@gmail.com>
Reviewed-by: Yuval Lifshitz <ylifshit@ibm.com>

diff --cc doc/radosgw/notifications.rst
index c635eb4dd5c14427e99d9c39c4cf3084bf0770df,54134823c3fa41e56d6205a7e4c09f9d01171b1a..d17c79d507e59acd29daf8560d497dd2ffdd9196
--- 1/doc/radosgw/notifications.rst
--- 2/doc/radosgw/notifications.rst
+++ b/doc/radosgw/notifications.rst
@@@ -103,9 -103,14 +103,12 @@@ Remove a topic by running the followin
  Notification Performance Statistics
  -----------------------------------
  
 -- ``pubsub_event_triggered``: a running counter of events that have at least one topic associated with them
 -- ``pubsub_event_lost``: a running counter of events that had topics associated with them, but that were not pushed to any of the endpoints
  - ``pubsub_push_ok``: a running counter, for all notifications, of events successfully pushed to their endpoints
  - ``pubsub_push_fail``: a running counter, for all notifications, of events that failed to be pushed to their endpoints
- - ``pubsub_push_pending``: the gauge value of events pushed to an endpoint but not acked or nacked yet
+ - ``pubsub_push_pending``: the gauge value of events pushed to an endpoint but
+   not acked or nacked yet. This does not include the notifications waiting in
+   the persistent queue. Only the notifications that are in flight in both
+   persistent and non-persistent cases are counted.
  
  .. note::