Re: Question about redo size in dump file and view

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Tue, 9 Jun 2009 19:59:59 +0100
Message-ID: <OqOdnahKvOOrLLPXnZ2dnUVZ8n2dnZ2d_at_bt.com>

<stevedhoward_at_gmail.com> wrote in message news:fcb1cd04-99ff-4af6-9611-e8bc34d7218d_at_g1g2000yqh.googlegroups.com... On Jun 7, 3:10 pm, "Jonathan Lewis" <jonat..._at_jlcomp.demon.co.uk> wrote:

<snip>

> From the redo record you posted, the 488 is (roughly):
> Record header:
> 12 byte
> Change vector 1
> 140 bytes redo for table insert
> Change vector 2
> 132 bytes of undo header transaction table slot acquisition
> Change vector 3
> 80 bytes to clear the undo header transaction table slot
> Change vector 4
> 132 bytes for recording the undo vector for the table change
>

Jonathan,

Have you documented your findings/research methodology on this type of thing? If so, I would love to read it.

Thanks,

Steve

Steve,

I just have a collection of notes that I've written over the years, nothing in a form I would publish. One of the other posters had given a link to some work by Riyaj, there's some more available from Eric S Emrick, and Julian Dyke has some very good material on his website.

-- 
Regards

Jonathan Lewis
http://jonathanlewis.wordpress.com

Author: Cost Based Oracle: Fundamentals
http://www.jlcomp.demon.co.uk/cbo_book/ind_book.html

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

Received on Tue Jun 09 2009 - 13:59:59 CDT