On Wed, 2005-10-05 at 09:53 +0300, Hannu Krosing wrote: > On T, 2005-10-04 at 11:10 -0400, Tom Lane wrote: > > Rod Taylor <[EMAIL PROTECTED]> writes: > > > The catch is that there are some other very active structures (like > > > pg_listener for Slony) which after a couple of hours without vacuuming > > > will quickly have the DB at an unreasonably high load (low tens) which > > > seems to all but halt the vacuum on the large structure. > > > > Yeah. We desperately need to reimplement listen/notify :-( ... that > > code was never designed to handle high event rates. > > Sure. But it handles amazingly well event rates up to a few hundred > events per second - given that pg_listener is cleaned up often enough.
Accomplishing the pg_listener cleanup often enough can be difficult in some circumstances. > It also seems that Slony can be modified to not use LISTEN/NOTIFY in > high load situations (akin to high performance network cards, which > switch from interrupt driven mode to polling mode if number of packets > per second reaches certain thresolds). I have other items in this database with high churn as well. Slony was just an example. -- ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
