Re: sequential scan unduly favored over text search gin index - Mailing list pgsql-performance

From Sushant Sinha
Subject Re: sequential scan unduly favored over text search gin index
Date
Msg-id 1308623134.1747.1.camel@dragflick
Whole thread Raw
In response to Re: sequential scan unduly favored over text search gin index  (Tomas Vondra <tv@fuzzy.cz>)
Responses Re: sequential scan unduly favored over text search gin index  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
>
> I agree the estimates are damn precise in this case (actually the
> estimates are exact). The problem is the planner thinks the seq scan is
> about 30% cheaper than the bitmap index scan.
>
> I guess you could poke the planner towards the bitmap scan by lowering
> the random_page_cost (the default value is 4, I'd say lowering it to 2
> should do the trick).

The numbers that I gave was after setting random_page_cost = 1.0 After
this I don't know what to do.

-Sushant.


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