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Home -> Community -> Mailing Lists -> Oracle-L -> Re: undotbs01.dbf just keeps growing
Jared,
It sure is nice to be missed. I'll make sure my secretary calls you about my future vacation plans...:)
You've nailed the problem. Autoextend, automatic undo and high undo retention is a recipe for high disk usage. The aum algorithm is such that preference is given to extending over reuse (especially since expire time propogation is a problem).
In order to find the length of the longest transaction, reference the v$undostat.maxquerylen value. Beware as there are known bugs with this view, so examine the output carefully to make sure it makes sense.
Daniel Fink
Jared Still wrote:
> The data file(s) for your undo tablespace is likely set
> as autoextend with an unlimited size.
>
> Run the attached script to check it.
>
> If so, you can use this to put a limit on it:
>
> alter database datafile '<your file name>' autoextend on next 200m
> maxsize 2000m;
>
> Adjust the numbers for your system.
>
> You should probably investigate why it continues to grow so large.
>
> I haven't yet converted our production databases to UNDO, having
> only recently migrated to 9i, so I don't have any useful advice
> past this.
>
> There are others that will be able to offer more for this. ( Dan
> Fink, where are you? This might even get Kirti to take a break
> from his book for a few minutes )
>
> HTH
>
> Jared
-- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Daniel Fink INET: Daniel.Fink_at_Sun.COM 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).Received on Mon Jan 05 2004 - 11:54:25 CST
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