Re: cpu_tuple_cost

From: Bruce Momjian
Subject: Re: cpu_tuple_cost
Date: ,
Msg-id: 200503150217.j2F2HqA01460@candle.pha.pa.us
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In response to: Re: cpu_tuple_cost  ("Greg Sabino Mullane")
List: pgsql-performance

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cpu_tuple_cost  (Daniel Schuchardt, )
 Re: cpu_tuple_cost  (Tom Lane, )
  Re: cpu_tuple_cost  ("Greg Sabino Mullane", )
   Re: cpu_tuple_cost  (Bruce Momjian, )
   Re: cpu_tuple_cost  (Tom Lane, )
    Re: cpu_tuple_cost  (Manfred Koizar, )
   Re: cpu_tuple_cost  (Josh Berkus, )
    Re: Changing the random_page_cost default (was: cpu_tuple_cost)  ("Greg Sabino Mullane", )
     Re: Changing the random_page_cost default (was: cpu_tuple_cost)  (Jeff Hoffmann, )
     Re: Changing the random_page_cost default (was: cpu_tuple_cost)  (Tom Lane, )
      Re: Changing the random_page_cost default (was:  (Mark Kirkwood, )
      Re: Changing the random_page_cost default (was: cpu_tuple_cost)  ("Greg Sabino Mullane", )
  Re: cpu_tuple_cost  (Daniel Schuchardt, )
 Re: cpu_tuple_cost  (Gregory Stark, )
  Re: cpu_tuple_cost  (David Brown, )
   Re: cpu_tuple_cost  (Greg Stark, )
    Re: cpu_tuple_cost  (Josh Berkus, )
     Re: cpu_tuple_cost  (Greg Stark, )
     Re: cpu_tuple_cost  (Tom Lane, )
      Re: cpu_tuple_cost  (Josh Berkus, )
       Re: cpu_tuple_cost  (Tom Lane, )
       Re: cpu_tuple_cost  (Michael Fuhr, )
 Re: cpu_tuple_cost  ("Magnus Hagander", )
  Re: cpu_tuple_cost  (Greg Stark, )

Greg Sabino Mullane wrote:
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> > Reducing random_page_cost is usually the best way to get the
> > planner to favor indexscans more.
>
> On that note, can I raise the idea again of dropping the default
> value for random_page_cost in postgresql.conf? I think 4 is too
> conservative in this day and age. Certainly the person who will
> be negatively impacted by a default drop of 4 to 3 will be the
> exception and not the rule.

Agreed.  I think we should reduce it at least to 3.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
                 |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073


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From: Josh Berkus
Date:
Subject: Re: cpu_tuple_cost
From: "Tambet Matiisen"
Date:
Subject: Re: One tuple per transaction