Re: [PERFORM] 8.4 optimization regression?

2011-08-30 Thread Mark Kirkwood
On 24/08/11 15:15, Tom Lane wrote: Mark Kirkwood writes: I am in the progress of an 8.3 to 8.4 upgrade for a customer. I seem to have stumbled upon what looks like a regression. The two databases (8.3.14 and 8.4.8) have identical tuning parameters (where that makes sense) and run on identical h

Re: [PERFORM] 8.4 optimization regression?

2011-08-30 Thread Mark Kirkwood
On 30/08/11 21:43, Grzegorz Jaśkiewicz wrote: 2011/8/29 Mark Kirkwood: I note from the commit message that the fix test case was from Grzegorz Jaskiewicz (antijoin against a small subset of a relation). I was not able to find this in the archives - Grzegorz do you recall the actual test case?

[PERFORM] IN or EXISTS

2011-08-30 Thread Andy Colson
Hi all, I have read things someplace saying not exists was better than not in... or something like that. Not sure if that was for in/exists and not in/not exists, and for a lot of records or not. Here is my setup: My website has a general table, let say 60k rows. Its mostly read-only. Ev

[PERFORM] Summaries on SSD usage?

2011-08-30 Thread Stefan Keller
Hi, I'm looking for summaries (or best practices) on SSD usage with PostgreSQL. My use case is mainly a "read-only" database. Are there any around? Yours, Stefan -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgr

Re: [PERFORM] Query optimization help

2011-08-30 Thread Ondrej Ivanič
Hi, 2011/8/30 Szymon Kosok : > 2011/8/30 Ondrej Ivanič : >> Could you please re-post your explain using this web site: >> http://explain.depesz.com/ and post links to Stackoverflow question? > > Here it is: http://explain.depesz.com/s/Iaa > >> - try to disable nested loop join (set enable_nestloop

Re: [PERFORM] 8.4 optimization regression?

2011-08-30 Thread Grzegorz Jaśkiewicz
2011/8/29 Mark Kirkwood : > I note from the commit message that the fix test case was from Grzegorz > Jaskiewicz (antijoin against a small subset of a relation).  I was not able > to find this in the archives - Grzegorz do you recall the actual test case? > I thought it might be useful for me to s

Re: [PERFORM] Query optimization help

2011-08-30 Thread Szymon Kosok
2011/8/30 Ondrej Ivanič : > Could you please re-post your explain using this web site: > http://explain.depesz.com/ and post links to Stackoverflow question? Here it is: http://explain.depesz.com/s/Iaa > - try to disable nested loop join (set enable_nestloop=off) Even worse performance (http://e