Thomas Kellerer <spam_eater@xxxxxxx> writes: > recently I have seen a Postgres configuration with the following values: > seq_page_cost = 0.5 > random_page_cost = 0.6 > Is there any advantage (or maybe disadvantage) compared to using e.g. 1.0 and 1.2? That reduces these costs relative to the cpu_xxx_cost ones. You'd get the same plans if you scaled *all* the planner cost parameters by the same amount, but changing only these two is the easiest way to reduce the significance of I/O relative to CPU costs. regression=# select name,setting from pg_settings where name like '%cost'; name | setting ----------------------+--------- cpu_index_tuple_cost | 0.005 cpu_operator_cost | 0.0025 cpu_tuple_cost | 0.01 parallel_setup_cost | 1000 parallel_tuple_cost | 0.1 random_page_cost | 4 seq_page_cost | 1 (7 rows) regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general