Locally-managed tablespaces (LMTS) in SAP
Hi,
I am working towards reorganizing most of my Production system tablespaces and I'm facing some issues due to the move from sapdba to brtools/brspace. SAP is recommending the use of BRSPACE for most of the DB admin tasks. While testing some reorganizations in my test box I noticed that BRSPACE is pushing me to recreate tablespaces as LMTS. I have some questions for the forum before I move into this:
- Has anybody done a complete migration from DMTS to LMTS? How smooth was the migration?
- What are the main advantages you've seen after migrating to LMTS?
I'm open to do it (given all the advantages listed) but I want to make sure I'm moving in the right direction.
Thanks in advance,
Eduardo L. Sanchez
SAP Basis Specialist
Lear Corp.
Software/Hardware used:
Software/Hardware used:
ASKED:
September 9, 2005 4:08 PM
UPDATED:
December 13, 2010 7:11 PM
Answer Wiki:
Hi,
Basically LMTS and DMTS concept belongs to Database. As this LMTS concept comes into database so that Admin can define or create tablespace according to his or organization requirement. Admin can give the various parameters by checking the database requirements. Its good to create LMTS as it works more efficiently than System Managed Table Spaces.
From 9i onwards this concept comes into Oracle database as only System Tablespace consists to System Manage Tablespaces and all the remaining tablespaces comes under LMTS. I haven't done migration exactly but I suppose you can do it by using the utility of Export/Import easily. Hope this helps.
Regards
Singh
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Hi
Here reorganizing means, basically it is performing exports and imports of all the tables in that particular tablespace, while performing import, if it is DMTS you will face space related issues as SAP tables are very huge in size, where as most of the space related issues can be avoid when we use LMTS. This is the major reason behind in forcing towards to LMTS. DMTS is old technology and Oracle strongly supports to go with LMTS as LMTS is having so many advantages over DMTS.
Few of the major advantages are gaining performance because of reduced hits on System Tablespace and reduced burden on Oracle DBA s.
Regards,
Abhishek
Senior Oracle DBA
Hello Eduardo, I’ve migrated an entire SAP system from dictionary managed TS to LMT (autoallocate). It took me 3 months to do that online. I used brtools. Basically, i created new locally tablespaces for tables and indexes and moved those objects to corresponding tablespaces. The only problem was after moving CDCLS table. We don’t know exactly whap happened, users reported to have missing documents. It seems SAP stores header documents in table CDCLS and detailed documents are stored in another table. We opened a ticket in SapService, they helped us to delete corrupted rows. But we lost those information. That was the only issue with online reorganization. I’ve working as Oracle DBA for 20 years, i’m not an SAP expert. But i can tell you that from the point of view of oracle database, LMT with lead to improve space usage in database. Hope it helps. Regards.