FreeLists / oracle-l / Re: experience with convert Dictionary managed tbs to LMT with dbms_space_admin

[zhu chao <zhuchao@xxxxxxxxx>]

Hi, Lex,
   Rebuild would be nice but as I said before, our database is pretty
big (1TB-3TB) and it is impossible to rebuild it without days's
downtime. The maximum downtime is 2 hours for us.  So we have to live
with current.
   
 ZimSbait, the thing you mentioned is critical for production box. I
am not sure what you was your exact problem. I don't have much
experience with the converted local managed tablespace, according to
metalink, it use the same extent management policy as dictionary
managed tablespace, so what is the difference?

Thanks

  

On 6/30/05, Lex de Haan <lex.de.haan@xxxxxxxxxxxxxx> wrote:
> LMTS is a *must* ... DMTS is dead. I only know good experiences.
> however, if you have the chance, create and populate the new LMTS tablespaces
> from scratch --
> don't migrate existing tablespaces. that leads (at the least) to suboptimal
> bitmap storage.
> 
> kind regards,
> 
> Lex.
> 
> ------------------------------------------------------------------
> Steve Adams Seminar http://www.naturaljoin.nl/events/seminars.html
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> -----Original Message-----
> From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On
> Behalf Of zhu chao
> Sent: Thursday, June 30, 2005 16:45
> To: Oracle-L@Freelists. Org (E-mail)
> Subject: experience with convert Dictionary managed tbs to LMT with
> dbms_space_admin
> 
> Hi, All,
>   We have some  pretty big OLTP database suffer from ST enqueue contention
> (size range from 1TB-3TB), because we use dictionary managed tablespace and
> without proper extent size when table/index/context index got created.
>    Now some indexes have tens of thousands of extents and whenever we drop 
> some
> unused objects(like not used index via index monitoring), we suffer from ST
> enqueue, even during normal business operation time.
> 
>  We plan to use dbms_space_admin to convert existing DMT tbs to LMT tbs, and I
> already did some test on test box and it seems very good and pretty fast.
>   Before do any change in production, ,I would like to ask you guys, if anyone
> has used it on big database and have any good/bad experience with it.
> 
> Thanks for sharing.
> Regards
> 
> 
> --
> Regards
> Zhu Chao
> www.cnoug.org
> --
> http://www.freelists.org/webpage/oracle-l
> 
> 
> 


-- 
Regards
Zhu Chao
www.cnoug.org
--
http://www.freelists.org/webpage/oracle-l