От: Joel Fradkin
Тема: Re: speed of querry?
Дата: ,
Msg-id: 000b01c54100$a68d2300$797ba8c0@jfradkin
(см: обсуждение, исходный текст)
Ответ на: Re: speed of querry?  (Dawid Kuroczko)
Ответы: Re: speed of querry?  (Dawid Kuroczko)
Список: pgsql-performance

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speed of querry?  ("Joel Fradkin", )
 Re: speed of querry?  (Richard Huxton, )
  Re: speed of querry?  ("Joel Fradkin", )
  Re: speed of querry?  (Tom Lane, )
   Re: speed of querry?  ("Joel Fradkin", )
    Re: speed of querry?  (Dawid Kuroczko, )
     Re: speed of querry?  ("Joel Fradkin", )
      Re: speed of querry?  (Dawid Kuroczko, )
       Re: speed of querry?  (Tom Lane, )
        Re: speed of querry?  ("Joel Fradkin", )
         Re: speed of querry?  ("Joel Fradkin", )
 Re: speed of querry?  ("Dave Held", )
  Re: speed of querry?  ("Joel Fradkin", )
   Re: speed of querry?  (Tom Lane, )
    Re: speed of querry?  ("Joel Fradkin", )
     Re: speed of querry?  (Tom Lane, )
 Re: speed of querry?  ("Dave Page", )
  Re: speed of querry?  ("Joel Fradkin", )

Josh from commandprompt.com had me alter the config to have
default_statistics_target = 250

Is this somehow related to what your asking me to do?
I did do an analyze, but have only ran the viw a few times.

Joel Fradkin

-----Original Message-----
From: Dawid Kuroczko [mailto:]
Sent: Thursday, April 14, 2005 9:21 AM
To: Joel Fradkin
Cc: PostgreSQL Perform
Subject: Re: [PERFORM] speed of querry?

On 4/14/05, Joel Fradkin <> wrote:
> I have done a vacuum and a vacuum analyze.
> I can try again for kicks, but it is not in production so no new records
are
> added and vacuum analyze is ran after any mods to the indexes.
>
> I am still pursuing Dell on why the monster box is so much slower then the
> desktop as well.

First thing:  Do something like:
ALTER TABLE tbljobtitle ALTER COLUMN clientnum SET STATISTICS 50;
make it for each column used, make it even higher than 50 for
many-values columns.
THEN make VACUUM ANALYZE;

Then do a query couple of times (EXPLAIN ANALYZE also :)), then do:
SET enable_seqscan = off;
and rerun the query -- if it was significantly faster, you will want to do:
SET enable_seqscan = on;
and tweak:
SET random_page_cost = 2.1;
...and play with values.  When you reach the random_page_cost which
suits your data, you will want to put it into postgresql.conf

I am sorry if it is already known to you. :)  Also, it is a rather
simplistic
approach to tuning PostgreSQL but it is worth doing.  Especially the
statistics part. :)

   Regards,
       Dawid



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