Re: High Redo Copy Contention

From: Andrew Mobbs <andrewm_at_chiark.greenend.org.uk>
Date: 03 Apr 2001 16:26:23 +0100 (BST)
Message-ID: <dCc*NRNSo@news.chiark.greenend.org.uk>

Anurag Minocha <AMinocha_at_herold.com> wrote:
>Hi,
>
>I am getting a High redo copy contention even after increasing the
>log_small_entry_max_size from 80 to 200. In fact I had a average redo size
>of 253 before increasing the log_small_entry_max_size parameter. yesterday
>after running the utlbstat/utlestat files I noticed that my average redo
>size (redo size/redo entries) has increased to 972.Why has this increased
>and how do I reduce the redo copy contention.
>
>PLEASE HELP.
Which version of Oracle is this? Certainly not 8i, as log_small_entry_max_size is obsolete there.

Have you tried tuning log_simultaneous_copies? You can usefully set this to 2x(#CPUs).

However, this may not help, see
<URL:http://www.ixora.com.au/tips/tuning/redo_latches.htm> for details, particularly the section towards the end of the article.

-- 
Andrew Mobbs - http://www.chiark.greenend.org.uk/~andrewm/

Received on Tue Apr 03 2001 - 10:26:23 CDT