On Mon, Jan 30, 2012 at 2:39 PM, Alessandro Gagliardi <alessandro@xxxxxxxx> wrote: > On Mon, Jan 30, 2012 at 1:25 PM, Josh Berkus <josh@xxxxxxxxxxxx> wrote: >> >> You can do "SHOW random_page_cost" yourself right now, too. >> > 4 > > I also tried "SHOW seq_page_cost" and that's 1. > > Looking > at http://www.postgresql.org/docs/current/static/runtime-config-query.html#GUC-RANDOM-PAGE-COST > I wonder if I should try reducing random_page_cost? > > Something that might help when it comes to advice on performance tuning is > that this database is used only for analytics. It's essentially a partial > replication of a production (document-oriented) database. So a lot of normal > operations that might employ a series of sequential fetches may not actually > be the norm in my case. Rather, I'm doing a lot of counts on data that is > typically randomly distributed. Yes try lowering it. Generally speaking, random page cost should always be >= seq page cost. Start with a number between 1.5 and 2.0 to start with and see if that helps. You can make it "sticky" for your user or database with alter user or alter database... -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
