Kevin Grittner wrote: > I've been lobbying management here for us to allocate some resources to > testing 8.3 once it hits beta. If it is approved, it might happen on a time > frame too short to get much feedback before the tests, so I'm throwing the > question out here now: what would people like us to bang on?
That would be great! > We're particularly interested in seeing what configuration changes we may > have to make to achieve optimal performance with the checkpoints and > background writer in the new release. When we first went to PostgreSQL our > biggest problem was that dirty buffers would accumulate in shared memory > until a checkpoint, and then overrun the controllers cache. This would cause > disk reads to queue up behind the writes, and queries which normally ran in a > millisecond or two were timing out at our renderers' 20 second limit. The > problem went away completely when we used a very aggressive background writer > configuration, to put the dirty pages in front of the OS file system right > away, so that its algorithms and the controller cache could deal with things > before they got out of hand. Yes, the load distributed checkpoints definitely should help with that. I'd like to see how well it works for you with the default bgwriter settings. -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match