Re: Some help on buffers and other performance tricks

On Wed, 9 Nov 2005 20:07:52 -0300
Alvaro Herrera <alvherre(at)commandprompt(dot)com> wrote:

> IMHO you should really be examining your queries _before_ you do any
> investment in hardware, because later those may prove unnecessary.

It all really depends on what you're doing. For some of the systems
I run, 4 GBs of RAM is *WAY* overkill, RAID 1+0 is overkill, etc.

In general I would slightly change the "order of operations" from:

1) Buy tons of RAM
2) Buy lots of disk I/O
3) Tune your conf
4) Examine your queries

to

1) Tune your conf
2) Spend a few minutes examining your queries
3) Buy as much RAM as you can afford
4) Buy as much disk I/O as you can
5) Do in depth tuning of your queries/conf

Personally I avoid planning my schema around my performance at
the start. I just try to represent the data in a sensible,
normalized way. While I'm sure I sub-consciously make decisions
based on performance considerations early on, I don't do any major
schema overhauls until I find I can't get the performance I need
via tuning.

Obviously there are systems/datasets/quantities where this won't
always work out best, but for the majority of systems out there
complicating your schema, maxing your hardware, and THEN tuning
is IMHO the wrong approach.

---------------------------------
Frank Wiles <frank(at)wiles(dot)org>
http://www.wiles.org
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