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Re: Why should such a simple query over indexed columns be so slow? - Mailing list pgsql-performance

From Alessandro Gagliardi
Subject Re: Why should such a simple query over indexed columns be so slow?
Date
Msg-id CAAB3BBJTQq8LR=RNgJepPhZnRNVPV19AMPgWe_22YeCK-wfzUw@mail.gmail.com
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In response to Re: Why should such a simple query over indexed columns be so slow?  (Scott Marlowe <scott.marlowe@gmail.com>)
Responses Re: Why should such a simple query over indexed columns be so slow?
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I set random_page_cost to 2 (with enable_seqscan on) and get the same performance I got with enable_seqscan off. 
So far so good. Now I just need to figure out how to set it globally. :-/

On Mon, Jan 30, 2012 at 1:45 PM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
On Mon, Jan 30, 2012 at 2:39 PM, Alessandro Gagliardi
<alessandro@path.com> wrote:
> Looking
> at http://www.postgresql.org/docs/current/static/runtime-config-query.html#GUC-RANDOM-PAGE-COST
> I wonder if I should try reducing random_page_cost?
>

Yes try lowering it.  Generally speaking, random page cost should
always be >= seq page cost.  Start with a number between 1.5 and 2.0
to start with and see if that helps.   You can make it "sticky" for
your user or database with alter user or alter database...

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