On Sat, 2006-09-23 at 17:14 -0700, Joshua D. Drake wrote: > >> Thank you: the problem was the effective_cache_size (which I hadn't > >> changed from the default of 1000). This machine doesn't have loads of > >> RAM, but I knocked it up to 65536 and now the query uses the index, > >> without having to change the statistics. > > > > Considering recent discussion about how 8.2 is probably noticeably more > > sensitive to effective_cache_size than prior releases, I wonder whether > > it's not time to adopt a larger default value for that setting. The > > current default of 1000 pages (8Mb) seems really pretty silly for modern > > machines; we could certainly set it to 10 times that without problems, > > and maybe much more. Thoughts? > > I think that 128 megs is probably a reasonable starting point. I know > plenty of people that run postgresql on 512 megs of ram. If you take > into account shared buffers and work mem, that seems like a reasonable > starting point. >
I agree, Adopting a higher effective_cache_size seems to be a good thing to do. (hmmm.... I must be dreaming again.... But I cannot stop wondering how it would be to have a smart "agent" that configures these values by analyzing the machine power and statistical values gathered from database usage......) ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq