On Tue, Apr 3, 2012 at 12:01 PM, Jon Nelson <jnelson+pgsql@xxxxxxxxxxx> wrote: > I have a situation that I'd like some help resolving. > Using PostgreSQL 8.4.<reasonably recent> on Linux, I have three things > coming together that cause me pain. I have a VIEW used by a bunch of > queries. Usually, these queries are fairly short (subsecond) but > sometimes they can be very long (days). I also update this view with > CREATE OR REPLACE VIEW every 15-30 minutes. What I observe, sometimes, > is this: > > 1. query A comes in. It's a big one. > 2. another process comes along, needs to update the view definition. > It issues create or replace view. It blocks on [1]. > 3. queries B through N come in, are blocked by [2], which is blocked by [1]. > 4. pandemonium! > > I can reduce (some) but not eliminate the need to update the view > multiple times a day. What might be some good ways to prevent queries > B through N blocking? > > Addendum: I can work around the issue by timing out and failing the > CREATE OR REPLACE VIEW (by canceling the query) after a short > duration, but is there a better way? Yeah -- this is just asking for trouble. Why do you have to replace the view every 30 minutes? Your solution is probably going to involve not doing that. merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
