Re: Massive Archive Logging

Some one else recently complained about the amount of extra redo generated after changing Oracle versions (in that case 7 to 8 I think).

Changing the size of the online redo log will not affect the amount of archive generated - the archive is just a copy of the online, and it doesn't matter whether you copy it 1M at a time or 100M at a time - the total copied will be the same (the performance of the database may be affected by checkpoints of course).

Possibilities -

Are you absolutely sure that the work done is still the same ? Are any users suddenly creating large table and indexes from time to time ?

Do you have any code to 'create table unrecoverable' or 'create index unrecoverable' that is suddenly not working unrecoverably ?

Do you have any SQL*Load in direct mode which are suddenly not loading unrecoverably, but are loading with redo generation.

Do you have any SQL*Load which are supposed to load with TRUNCATE, but now appear to be loading with DELETE ?

Check the redo wastage (v$sysstat) - is most of the increase redo wastage, or is it really redo ? Do you have stats pre-upgrade.

--

Jonathan Lewis
Yet another Oracle-related web site: www.jlcomp.demon.co.uk

Mitchell Loren wrote in message <376841FB.A96E3110_at_home.com>...
>I recently moved my db from 7.3.2 (AIX 4.1:RS6000) to 7.3.4 (AIX 4.3:IBM
>SP2). Before I moved the db I had about 6 GIG of archive logs produced
>in a 24 hour period ( 5 groups of redo logs, 2 members each, 5M each).
>After I moved to 7.3.4 archiving went up to 18 GIG per 24 hours. The
>amount of transactions stayed the same.
>
>To remedy the situation I added 2 more groups and resized the redo logs
>to 30M each. I also set the log_checkpoint_interval > redo log size.
>Unfortunately, this did not help. Actually the total amount of archive
>logs went up to over 25 GIG in a 24 hour period.
>
>Has anyone experienced this type of massive archiving. I don't think
>further increasing the redo size will help. Rather it is some process
>of 7.3.4 which functions differently than 7.3.2. Any suggestions ?
Received on Thu Jun 17 1999 - 02:33:08 CDT