From: Sushant Sinha <sushant354@gmail.com>
To: Tomas Vondra <tv@fuzzy.cz>
Cc: pgsql-performance@postgresql.org
Subject: Re: sequential scan unduly favored over text search gin index
Date: Tue, 21 Jun 2011 07:55:34 +0530
Message-ID: <1308623134.1747.1.camel@dragflick> (raw)
In-Reply-To: <4DFF990F.8080906@fuzzy.cz>
References: <1308584339.2488.12.camel@dragflick>
<4DFF27C5020000250003E9A4@gw.wicourts.gov>
<1308585840.2488.13.camel@dragflick>
<4DFF990F.8080906@fuzzy.cz>
>
> 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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To: pgsql-performance@postgresql.org
Cc: sushant354@gmail.com, tv@fuzzy.cz
Subject: Re: sequential scan unduly favored over text search gin index
In-Reply-To: <1308623134.1747.1.camel@dragflick>
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