Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.misc -> Re: Never rebuild Indexes?

Re: Never rebuild Indexes?

From: DA Morgan <damorgan_at_psoug.org>
Date: Sun, 04 Feb 2007 14:07:22 -0800
Message-ID: <1170626842.215479@bubbleator.drizzle.com>


Oradba Linux wrote:

> DA Morgan wrote:

>> Oradba Linux wrote:
>>> We are running a 4 node RAC on RHEL 3.0. We have a table with 300mil
>>> rows that has an pk index upto 12Gb and we rebuilt it it came down to
>>> 6g. The data into this table was loaded with concurrent inserts from
>>> different sessions. This table is on ASSM tablespace. Same thing with
>>> many other indexes.
>>
>> Given it is a RAC cluster I must ask ...
>> What type of index?
> B*Tree

>> Does the primary key include the instance identifier?
> No

>> What performance metric indicates the rebuild is accomplishing anything?
> None.

Then I would recommend a couple of things.

  1. Learn about indexing strategies for RAC. There are white papers written on the subject and low on my list of index types for a RAC cluster would be a normal B*Tree. Doesn't mean I wouldn't use them but not my first choice due to contention.
  2. Same comment as above. Look for papers written by Kirk McGowan who is Technical Director of Oracle's RAC Pack.
  3. Then my recommendation would be to push yourself back away from the keyboard. Making changes without metrics generally produces changes: Little else.

You might want to bookmark this website: http://www.oracleracsig.org/

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org
Received on Sun Feb 04 2007 - 16:07:22 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US