Re: Performance Tuning - Mailing list pgsql-general

From Darryl W. DeLao Jr.
Subject Re: Performance Tuning
Date
Msg-id 25274f460602171201u60f19c1fob2bad3cd49201d31@mail.gmail.com
Whole thread Raw
In response to Re: Performance Tuning  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Performance Tuning  (Scott Marlowe <smarlowe@g2switchworks.com>)
List pgsql-general
Running ver 7.3.10 in RHEL 3.0 ES.  If I change shared buffers, dont i have to change max connections as well? 

On 2/17/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
"Darryl W. DeLao Jr." <ddelao@gmail.com> writes:
> I have max_connections set to 512, with shared buffers set to 1024.  If I
> set this any higher, postgres will not start.  But, it seems that this
> setting is not enough.  Though the server runs fine, certain queries for
> reports are taking anywhere from 40 to 55 seconds, and the CPU is only
> topping out at 25%.  Is there a way to make this better?

You really really want shared_buffers higher --- 10000 or so would be
reasonable.  (Which PG version are you running?  If 8.1 you might want
higher than that.)

Fix the kernel's SHMMAX setting to let you do this.

After that, you probably want to read the archives of the
pgsql-performance list a bit.  You likely have a standard query-tuning
problem, but you've not said enough to let anyone help you.

                       regards, tom lane

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