От: Kevin Grittner
Тема: Re: query optimization
Дата: ,
Msg-id: 4F994C5A02000025000473FD@gw.wicourts.gov
(см: обсуждение, исходный текст)
Ответ на: query optimization  (Richard Kojedzinszky)
Список: pgsql-performance

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query optimization  (Richard Kojedzinszky, )
 Re: query optimization  ("Kevin Grittner", )
 Re: query optimization  (Tom Lane, )
  Re: query optimization  (Thomas Kellerer, )
   Re: query optimization  (Tom Lane, )
    Re: query optimization  (Andrew Dunstan, )
  Re: query optimization  (Richard Kojedzinszky, )

Richard Kojedzinszky <> wrote:

> tuning our installation to not to use sequence scans in this case?

Make sure effective_cache_size is set to the sum of shared_buffers
and whatever your OS shows as usable for caching.  Try adjusting
cost factors: maybe random_page_cost between 1 and 2, and
cpu_tuple_cost between 0.03 and 0.05.

-Kevin


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