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