Re: [PERFORM] [Again] Postgres performance problem

2007-09-12 Thread Frank Schoep
On Sep 12, 2007, at 9:07 PM, Scott Marlowe wrote: On 9/12/07, Mikko Partio <[EMAIL PROTECTED]> wrote: … Aren't you mixing up REINDEX and CLUSTER? … Either one does what a vacuum full did / does, but generally does it better. On topic of REINDEX / VACUUM FULL versus a CLUSTER / VACUUM ANALY

Re: [PERFORM] Bad planner decision - bitmap scan instead of index

2007-08-17 Thread Frank Schoep
On Aug 17, 2007, at 5:23 PM, Michael Stone wrote: On Fri, Aug 17, 2007 at 10:43:18AM +0200, Frank Schoep wrote: On Aug 17, 2007, at 9:28 AM, hubert depesz lubaczewski wrote: (cost=0.00..37612.76 rows=14221 width=48) (actual time=0.125..13.686 rows=2000 loops=1) [snip] I'm not an expe

Re: [PERFORM] Bad planner decision - bitmap scan instead of index

2007-08-17 Thread Frank Schoep
On Aug 17, 2007, at 9:28 AM, hubert depesz lubaczewski wrote: … try to change the query to: SELECT * FROM movies WHERE letter = 'T' ORDER BY letter ASC, name ASC LIMIT 100 OFFSET 1900; Thanks for the suggestion, however executing this query takes even longer regardless of work_mem. The que

Re: [PERFORM] Bad planner decision - bitmap scan instead of index

2007-08-16 Thread Frank Schoep
On Aug 16, 2007, at 7:01 PM, Tom Lane wrote: … Why is the sort step so slow? Sorting a mere 13k rows shouldn't take very long. Maybe you are overrunning work_mem and it's falling back to a disk sort ... what is work_mem set to? By default work_mem is set to "1024". Increasing the value to "819

[PERFORM] Bad planner decision - bitmap scan instead of index

2007-08-16 Thread Frank Schoep
at does not seem elegant, I'd rather have the query planner make better decisions - I could try and test what 8.2 does if someone expects the results to be different, but I can't yet upgrade my production servers to 8.2 - am I just running into a corner case which falls outside of the pl