On Mon, Mar 27, 2006 at 03:34:32PM +0200, G?briel ?kos wrote: > Hi, > > I guess this is an age-old 100times answered question, but I didn't find > the answer to it yet (neither in the FAQ nor in the mailing list archives). > > Question: I have a table with 2.5M rows. count(*) on this table is > running 4 minutes long. (dual opteron, 4gig ram, db on 4 disk raid10 > array (sata, not scsi)) Is this normal? How could I make it run faster? > Maybe make it run faster for the 2nd time? Which parameters should I > change in postgresql.conf and how?
First, count(*) on PostgreSQL tends to be slow because you can't do index covering[1]. But in this case, I'd bet money that if it's taking 4 minutes something else is wrong. Have you been vacuuming that table frequently enough? What's SELECT relpages FROM pg_class WHERE relname='tablename' show? [1] http://www.pervasive-postgres.com/lp/newsletters/2006/Insights_postgres_Feb.asp#5 -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
