On Thu, Sep 10, 2009 at 9:57 AM, Robert Haas <robertmh...@gmail.com> wrote:
> 2009/9/10 <t...@fuzzy.cz>: > >> Playing around with seq_page_cost (1) and random_page_cost (1), I can > get > >> the correct index selected. Applying those same settings to our > production > >> server does not produce the optimal plan, though. > > > > I doubt setting seq_page_cost and random_page_cost to the same value is > > reasonable - random access is almost always more expensive than > sequential > > access. > > If the data figures to be read from the OS cache, it's very > reasonable, and the right value is somewhere in the 0.05 - 0.10 range. > > For the most part, it will indeed be cached. Thanks for the tip on the values.
