Re: Strangely Variable Query Performance

От: Steve
Тема: Re: Strangely Variable Query Performance
Дата: ,
Msg-id: Pine.GSO.4.64.0704121925280.17955@kittyhawk.tanabi.org
(см: обсуждение, исходный текст)
Ответ на: Re: Strangely Variable Query Performance  (Tom Lane)
Список: pgsql-performance

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Slow Postgresql server  (Jason Lustig, )
 Re: Slow Postgresql server  (Dennis Bjorklund, )
 Re: Slow Postgresql server  (Jeff Frost, )
 Re: Slow Postgresql server  (Ron, )
  Re: Slow Postgresql server  (Guido Neitzer, )
   Re: Slow Postgresql server  (Ron, )
    Re: Slow Postgresql server  (Guido Neitzer, )
     Re: Slow Postgresql server  (Scott Marlowe, )
      Re: Slow Postgresql server  (Jeff Frost, )
       Re: Slow Postgresql server  (Carlos Moreno, )
       Strangely Variable Query Performance  (Steve, )
        Re: Strangely Variable Query Performance  (Tom Lane, )
         Re: Strangely Variable Query Performance  (Steve, )
          Re: Strangely Variable Query Performance  (Tom Lane, )
           Re: Strangely Variable Query Performance  (Steve, )
            Re: Strangely Variable Query Performance  (Tom Lane, )
             Re: Strangely Variable Query Performance  (Steve, )
        Re: Strangely Variable Query Performance  (Scott Marlowe, )
         Re: Strangely Variable Query Performance  (Steve, )
          Re: Strangely Variable Query Performance  (Scott Marlowe, )
           Re: Strangely Variable Query Performance  (Steve, )
           Re: Strangely Variable Query Performance  (Tom Lane, )
            Re: Strangely Variable Query Performance  (Steve, )
             Re: Strangely Variable Query Performance  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
             Re: Strangely Variable Query Performance  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
               Re: Strangely Variable Query Performance  (Tom Lane, )
                Re: Strangely Variable Query Performance  (Steve, )
                 Re: Strangely Variable Query Performance  (Tom Lane, )
                  Re: Strangely Variable Query Performance  (Steve, )
                   Re: Strangely Variable Query Performance  (Tom Lane, )
                   Re: Strangely Variable Query Performance  (Tom Lane, )
                    Re: Strangely Variable Query Performance  (Steve, )
                     Re: Strangely Variable Query Performance  (Tom Lane, )
                      Fwd: Strangely Variable Query Performance  ("Robins Tharakan", )
                     choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
                      Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Alvaro Herrera, )
                       Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
                       Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
              Re: Strangely Variable Query Performance  (Steve, )
             Re: [HACKERS] choose_bitmap_and again (was Re: Strangely Variable Query Performance)  (Tom Lane, )
 Re: Slow Postgresql server  (Jeff Frost, )
  Re: Slow Postgresql server  (Jason Lustig, )
   Re: Slow Postgresql server  (Guido Neitzer, )
 Fwd: Strangely Variable Query Performance  (Robins, )
  Re: Fwd: Strangely Variable Query Performance  (Tom Lane, )

It's a redhat enterprise machine running AMD x64 processors.

Linux ers3.dddcorp.com 2.6.9-42.0.10.ELsmp #1 SMP Fri Feb 16 17:13:42 EST
2007 x86_64 x86_64 x86_64 GNU/Linux

It was compiled by me, straight up, nothing weird at all, no odd compiler
options or wahtever :)

So yeah :/ I'm quite baffled as well,

Talk to you later,

Steve


On Thu, 12 Apr 2007, Tom Lane wrote:

> Steve <> writes:
>> Here's my planner parameters:
>
> I copied all these, and my 8.2.x still likes the bitmap scan a lot
> better than the seqscan.  Furthermore, I double-checked the CVS history
> and there definitely haven't been any changes in that area in REL8_2
> branch since 8.2.3.  So I'm a bit baffled.  Maybe the misbehavior is
> platform-specific ... what are you on exactly?  Is there anything
> nonstandard about your Postgres installation?
>
>             regards, tom lane
>


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От: Tom Lane
Дата:
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