Re: anti-join chosen even when slower than old plan

От: Kevin Grittner
Тема: Re: anti-join chosen even when slower than old plan
Дата: ,
Msg-id: 4CD983E002000025000374D7@gw.wicourts.gov
(см: обсуждение, исходный текст)
Ответ на: Re: anti-join chosen even when slower than old plan  (Tom Lane)
Список: pgsql-performance

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anti-join chosen even when slower than old plan  ("Kevin Grittner", )
 Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
  Re: anti-join chosen even when slower than old plan  (Tom Lane, )
   Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
 Re: anti-join chosen even when slower than old plan  (Tom Lane, )
  Re: anti-join chosen even when slower than old plan  (Grzegorz Jaśkiewicz, )
  Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
   Re: anti-join chosen even when slower than old plan  (Tom Lane, )
   Re: anti-join chosen even when slower than old plan  (Robert Haas, )
    Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
     Re: anti-join chosen even when slower than old plan  (Tom Lane, )
      Re: anti-join chosen even when slower than old plan  (Robert Haas, )
       Re: anti-join chosen even when slower than old plan  (Kenneth Marshall, )
        Re: anti-join chosen even when slower than old plan  (Mladen Gogala, )
         Re: anti-join chosen even when slower than old plan  (Kenneth Marshall, )
         Re: anti-join chosen even when slower than old plan  (Bob Lunney, )
     Re: anti-join chosen even when slower than old plan  (Mladen Gogala, )
      Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
       Re: anti-join chosen even when slower than old plan  (Mladen Gogala, )
        Re: anti-join chosen even when slower than old plan  (Tom Lane, )
         Re: anti-join chosen even when slower than old plan  (Mladen Gogala, )
         Re: anti-join chosen even when slower than old plan  (Bruce Momjian, )
        Re: anti-join chosen even when slower than old plan  (Craig James, )
       Re: anti-join chosen even when slower than old plan  (Robert Haas, )
        Re: anti-join chosen even when slower than old plan  (Tom Lane, )
         Re: anti-join chosen even when slower than old plan  (Tom Lane, )
          Re: anti-join chosen even when slower than old plan  (Robert Haas, )
           Re: anti-join chosen even when slower than old plan  (Tom Lane, )
            Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
            Re: anti-join chosen even when slower than old plan  (Robert Haas, )
             Re: anti-join chosen even when slower than old plan  (<>, )
              Re: anti-join chosen even when slower than old plan  (Kenneth Marshall, )
             Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
              Re: anti-join chosen even when slower than old plan  (Robert Haas, )
               Re: anti-join chosen even when slower than old plan  (Tom Lane, )
                Re: anti-join chosen even when slower than old plan  (Robert Haas, )
                Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
                 Re: anti-join chosen even when slower than old plan  ("Marc Mamin", )
                  Re: anti-join chosen even when slower than old plan  (bricklen, )
                  Re: anti-join chosen even when slower than old plan  (Robert Haas, )
                Re: anti-join chosen even when slower than old plan  (Bruce Momjian, )
                 Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
                  Re: anti-join chosen even when slower than old plan  (Robert Haas, )
                   Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
                   Re: anti-join chosen even when slower than old plan  (Bruce Momjian, )
             Re: anti-join chosen even when slower than old plan  (Bruce Momjian, )
              Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
            Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
             Re: anti-join chosen even when slower than old plan  (Vitalii Tymchyshyn, )
              Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
               Re: anti-join chosen even when slower than old plan  (Vitalii Tymchyshyn, )
                Re: anti-join chosen even when slower than old plan  (Cédric Villemain, )
          Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
           Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
           Re: anti-join chosen even when slower than old plan  (Tom Lane, )
            Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )
            Re: anti-join chosen even when slower than old plan  (Jon Nelson, )
          Re: anti-join chosen even when slower than old plan  (Andres Freund, )
         Re: anti-join chosen even when slower than old plan  (Robert Haas, )
          Re: anti-join chosen even when slower than old plan  (Tom Lane, )
    Re: anti-join chosen even when slower than old plan  (Віталій Тимчишин, )
 Re: anti-join chosen even when slower than old plan  ("Kevin Grittner", )

Tom Lane <> wrote:

> However, you'd have to be spending a lot of time chasing through
> long HOT chains before that would happen enough to make this a
> hotspot...

That makes it all the more mysterious, then.  These tables are
insert-only except for a weekly delete of one week of the oldest
data.  The parent table, with the date, is deleted first, then this
table deletes "where not exists" a corresponding parent.  I can't
see how we'd ever have a HOT chain in these tables.

Is there anything in particular you'd like me to check?

-Kevin


В списке pgsql-performance по дате сообщения:

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Дата:
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От: Grzegorz Jaśkiewicz
Дата:
Сообщение: Re: anti-join chosen even when slower than old plan