Re: LISTEN/NOTIFY ultra slow speed

=?UTF-8?B?0JDRgNGB0LXQvSDQkNGA0YPRgtGO0L3Rj9C9?= <arutar@bk.ru> writes:
>     Hello! I'm having trouble with LISTEN/NOTIFY speed. Now I have about 100-200 (few?) clients who are actively
messaging.But recently I started to notice a drop in speed. Changing the log_min_duration_statement parameter did not
showslow queries in the log. 
>     As it turned out, the pg_notify(text ,text) function
>           or the
>           NOTIFY text, 'text' queries takes an extremely long time (0.7-1.5sec),
>     but the select pg_notification_queue_usage() query always returns 0.

What PG version is this exactly?  What is in $PGDATA/pg_notify/ ?

            regards, tom lane