Re: Performance problems with 9.2.15

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От Johan Fredriksson
Тема Re: Performance problems with 9.2.15
Дата
Msg-id 574855F5.8070603@kth.se
обсуждение исходный текст
Ответ на Re: Performance problems with 9.2.15  (Tom Lane)
Ответы Re: Performance problems with 9.2.15  (Steve Crawford)
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Дерево обсуждения
Performance problems with 9.2.15  (Johan Fredriksson, )
 Re: Performance problems with 9.2.15  (Tom Lane, )
  Re: Performance problems with 9.2.15  (Johan Fredriksson, )
   Re: Performance problems with 9.2.15  (Steve Crawford, )
  Re: Performance problems with 9.2.15  (Johan Fredriksson, )
   Re: Performance problems with 9.2.15  (Johan Fredriksson, )
    Re: Performance problems with 9.2.15  (Johan Fredriksson, )
     Re: Performance problems with 9.2.15  (Claudio Freire, )
      Re: Performance problems with 9.2.15  ("David G. Johnston", )
       Re: Performance problems with 9.2.15  (Claudio Freire, )
        Re: Performance problems with 9.2.15  (Johan Fredriksson, )
         Re: Performance problems with 9.2.15  (Johan Fredriksson, )
          Re: Performance problems with 9.2.15  (Mark Kirkwood, )
           Re: Performance problems with 9.2.15  (Johan Fredriksson, )
> The rowcount estimates from 9.2 seem greatly different from the 8.4 plan.
> Did you remember to ANALYZE all the tables after migrating?   Maybe there
> were some table-specific statistics targets that you forgot to transfer
> over?

No, I did not. Honestly I though everything would be transfered with a
dump/restore procedure. Unfortunatly running ANALYZE VERBOSE on all
involved tables did not really improve anything.

 > In any case, the 9.2 plan looks like garbage-in-garbage-out to
> me :-( ... without estimates at least a little closer to reality, the
> planner is unlikely to do anything very sane.
>
> (BTW, I wonder why you are moving only to 9.2 and not something more
> recent.)

Well, 9.2.15 is what comes bundled with RHEL 7, so I decided to go with
that to avoid dependency issues. But I could install a more fresh
version from scratch if that would solve my problem.


         / Eskil



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