On 06/25/2015 07:50 AM, Tom Lane wrote: > To do that, we'd have to change the semantics of the 'waiting' column so > that it becomes true for non-heavyweight-lock waits. I'm not sure whether > that's a good idea or not; I'm afraid there may be client-side code that > expects 'waiting' to indicate that there's a corresponding row in > pg_locks. If we're willing to do that, then I'd be okay with > allowing wait_status to be defined as "last thing waited for"; but the > two points aren't separable.
Speaking as someone who writes a lot of monitoring and alerting code, changing the meaning of the waiting column is OK as long as there's still a boolean column named "waiting" and it means "query blocked" in some way. Users are used to pg_stat_activity.waiting failing to join against pg_locks ... for one thing, there's timing issues there. So pretty much everything I've seen uses outer joins anyway. -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
