Re: db block Size for Indexes Tablespaces in 9.2 ?

Sorry,

It was a rhetorical question.

Detailed results come under the heading
of company confidential - generic results come under the heading of repetition.

You just have to list the set of point (see my earlier point) about why smaller or larger blocks MIGHT make a difference that you could expect to notice, then figure out if any of those points are relevant to your system, then devise a realistic test to find out if any hypothetical benefit turns into a real benefit.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Coming soon a new one-day tutorial:
Cost Based Optimisation
(see http://www.jlcomp.demon.co.uk/tutorial.html )

Next Seminar dates:
(see http://www.jlcomp.demon.co.uk/seminar.html )

____England______January 21/23

The Co-operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html

-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 23 December 2002 10:24

>Hi Jonathan
>
>Would like to have Tests done for BOTH Small & Big DB_BLOCK_SIZE ,
>if possible , as mentioned below
>
>Thanks
>
>-----Original Message-----
>Sent: Wednesday, December 18, 2002 4:50 PM
>To: Multiple recipients of list ORACLE-L
>
>
>
>I think there are too many generic arguments
>available for picking the 'right' block size for
>your indexes.
>
>The one that is most appropriate is likely to
>depend on the nature of the activity (load
>vs. query), nature of the index (unique,
>nearly unique, far from unique), data clustering,
>order of data arrival, frequency of data arrival,
>pattern of data deletion/update, stability of volume,
>nature of queries (big or small range scans),
>potential of modifying number of branches,
>buffering effects, and whether or not you are
>using a filesystem with or without direct i/o.
>
>Given another 10 minutes I might come up
>with a few more ideas.
>
>Your strategy should be to identify the extreme,
>and critical, characteristics of your system and
>play to them - small block size may be appropriate,
>reverse indexes may be appropriate, getting rid of
>the synthetic key that is likely to cause a problem
>may be appropriate. But don't assume that anything
>as trivial as tweaking a block size is a driving
>feature of making your index work well.
>
>Which test case would you like to see - the one
>I did for company X that showed they needed a
>small block size, or the one I did for company Y
>that showed they needed a large block size ?
>
>
>Regards
>
>Jonathan Lewis
>http://www.jlcomp.demon.co.uk
>
>Coming soon a new one-day tutorial:
>Cost Based Optimisation
>(see http://www.jlcomp.demon.co.uk/tutorial.html )
>
>Next Seminar dates:
>(see http://www.jlcomp.demon.co.uk/seminar.html )
>
>____England______January 21/23
>
>
>The Co-operative Oracle Users' FAQ
>http://www.jlcomp.demon.co.uk/faq/ind_faq.html
>
>
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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).