Re: Logarithmic change (decrease) in performance

From: "Jim C(dot) Nasby" <jnasby(at)pervasive(dot)com>
To: Ron Peacetree <rjpeace(at)earthlink(dot)net>
Cc: Matthew Nuzum <mattnuzum(at)gmail(dot)com>, newz(at)bearfruit(dot)org, Postgresql Performance list <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Logarithmic change (decrease) in performance
Date: 2005-10-04 20:19:33
Message-ID: 20051004201933.GT40138@pervasive.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

On Wed, Sep 28, 2005 at 06:03:03PM -0400, Ron Peacetree wrote:
> 1= keep more of the data set in RAM
> 2= increase the size of your HD IO buffers
> 3= make your RAID sets wider (more parallel vs sequential IO)
> 4= reduce the atomic latency of your RAID sets
> (time for Fibre Channel 15Krpm HD's vs 7.2Krpm SATA ones?)
> 5= make sure your data is as unfragmented as possible
> 6= change you DB schema to minimize the problem
> a= overall good schema design
> b= partitioning the data so that the system only has to manipulate a
> reasonable chunk of it at a time.

Note that 6 can easily swamp the rest of these tweaks. A poor schema
design will absolutely kill any system. Also of great importance is how
you're using the database. IE: are you doing any row-by-row operations?

> In many cases, there's a number of ways to accomplish the above.
> Unfortunately, most of them require CapEx.
>
> Also, ITRW world such systems tend to have this as a chronic
> problem. This is not a "fix it once and it goes away forever". This
> is a part of the regular maintenance and upgrade plan(s).

And why DBA's typically make more money that other IT folks. :)
--
Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Jim C. Nasby 2005-10-04 20:31:02 Re: Comparative performance
Previous Message Jim C. Nasby 2005-10-04 18:55:13 Re: Slow concurrent update of same row in a given table