From: | "Guillaume Smet" <guillaume(dot)smet(at)gmail(dot)com> |
---|---|
To: | pgsql-bugs <pgsql-bugs(at)postgresql(dot)org> |
Subject: | 8.2 and 8.3 postgresql.conf oddity |
Date: | 2008-01-23 10:50:38 |
Message-ID: | 1d4e0c10801230250w8bf439cp81897f65857ef1a5@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-bugs |
Hi -bugs,
I just noticed something odd in the Planner constants part of the 8.2
and 8.3 postgresql.conf:
# - Planner Cost Constants -
#seq_page_cost = 1.0 # measured on an arbitrary scale
#random_page_cost = 4 # same scale as above
#cpu_tuple_cost = 0.01 # same scale as above
#cpu_index_tuple_cost = 0.005 # same scale as above
#cpu_operator_cost = 0.0025 # same scale as above
The "same scale as above" while we have an "arbitrary scale" on the
first line is a bit weird.
8.1 was:
random_page_cost = 2 # units are one sequential page fetch
# cost
cpu_tuple_cost = 0.01 # (same)
cpu_index_tuple_cost = 0.001 # (same)
cpu_operator_cost = 0.0025 # (same)
Which seems better.
AFAIK, the unit of random_page_cost and cpu_*_cost is now seq_page_cost.
--
Guillaume
From | Date | Subject | |
---|---|---|---|
Next Message | Dave Page | 2008-01-23 11:12:11 | Re: BUG #3895: Access denied |
Previous Message | Arjan Bolmer | 2008-01-23 10:36:52 | BUG #3895: Access denied |