Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine

От: Alvaro Herrera
Тема: Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine
Дата: ,
Msg-id: 20100415202405.GL7259@alvh.no-ip.org
(см: обсуждение, исходный текст)
Ответ на: Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Tom Lane)
Ответы: Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus)
Список: pgsql-performance

Скрыть дерево обсуждения

Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus, )
 Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Alvaro Herrera, )
  Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Tom Lane, )
   Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Alvaro Herrera, )
    Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus, )
     Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Tom Lane, )
      Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus, )
       Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus, )
        Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Alvaro Herrera, )
         Re: Autovaccum with cost_delay does not complete on one solaris 5.10 machine  (Josh Berkus, )

Tom Lane wrote:
> Alvaro Herrera <> writes:
> > We don't call pollsys anywhere.  Something in Solaris must be doing it
> > under the hood.
>
> pg_usleep calls select(), and some googling indicates that select() is
> implemented as pollsys() on recent Solaris versions.  So Josh's
> assumption that those are delay calls seems plausible.  But it shouldn't
> be sleeping after each page with normal cost_delay parameters, should it?

Certainly not ... The only explanation would be that the cost balance
gets over the limit very frequently.  So one of the params would have to
be abnormally high (vacuum_cost_page_hit, vacuum_cost_page_miss,
vacuum_cost_page_dirty).

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.


В списке pgsql-performance по дате сообщения:

От: Dave Crooke
Дата:
Сообщение: SOLVED: Re: HELP: How to tame the 8.3.x JDBC driver with a biq guery result set
От: Віталій Тимчишин
Дата:
Сообщение: Planner not using column limit specified for one column for another column equal to first