RE: Correct way to accuse BCHR tuning method (Was: Hit ratio)

Hi Yong
> I agree that "It's not the ratio that needs condemning, it's
> the advice about..." What I disagree is the wrong educational
> tool people on public forums have recently used again and
> again to show the inadequacy of the BCHR tuning method.

The thing is most people who have used this demonstration, use it for 2 reasons

1. It is immediately recognised and empathised with by the audience and
2. It is easily explained. "How does it work, by doing pointless io, hmmm I wonder if that is a problem with my real system."

You are of course in principle correct that one could use the same technique against other ratios, my suggestion would be that this might also be appropriate for similar reasons. My CPU is 75% utilized on my web server, I wonder does this mean it is well specified or that I am doing pointless cpu work?

If people are merely saying "the bchr is useless, here is a script that will create one for you" then I would agree with you, but in my experience the argument is more cogent than that.

Niall

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Niall Litchfield
  INET: niall.litchfield_at_dial.pipex.com

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).