Ticket #8537: 8537.diff

docs/topics/http/sessions.txt

@@ -188 +188 @@
       different values:
 
             * If ``value`` is an integer, the session will expire after that
-              many seconds of inactivity. For example, calling
+              many seconds of inactivity (inactivity constitutes time in which
+              request.session is not modified, simply reading from a session
+              is not considered activity). For example, calling
               ``request.session.set_expiry(300)`` would make the session expire
-              in 5 minutes.
+              in 5 minutes, assuming the session is not written to before then.
 
             * If ``value`` is a ``datetime`` or ``timedelta`` object, the
               session will expire at that specific date/time.