Re: ported application having performance issues

From: John Mendenhall <john(at)surfutopia(dot)net>
To: Dennis Bjorklund <db(at)zigo(dot)dhs(dot)org>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: ported application having performance issues
Date: 2005-07-02 00:52:37
Message-ID: 20050702005237.GA26087@calvin.surfutopia.net
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Dennis,

On Fri, 01 Jul 2005, Dennis Bjorklund wrote:

> On Thu, 30 Jun 2005, John Mendenhall wrote:
>
> > Our setting for effective_cache_size is 2048.
> >
> > random_page_cost = 4, effective_cache_size = 2048 time approximately 4500ms
> > random_page_cost = 3, effective_cache_size = 2048 time approximately 1050ms
> > random_page_cost = 3, effective_cache_size = 4096 time approximately 1025ms
>
> The effective_cache_size still looks small. As a rule of tumb you might
> want effective_cache_size to be something like 1/2 or 2/3 of your total
> memory. I don't know how much you had, but effective_cache_size = 4096 is
> only 32M.
>
> shared_buffers and effective_cache_size is normally the two most important
> settings in my experience.

I have increased the effective_cache_size to 16384 (128M). I have kept
random_page_cost at 3 for now. This appears to give me the performance
I need at this time.

In the future, we'll look at other methods of increasing the
performance.

Thank you all for all your suggestions.

JohnM

--
John Mendenhall
john(at)surfutopia(dot)net
surf utopia
internet services

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