RMAN SLOW PERFORMANCE ON EXIT

Hello Readers,

When it comes to backup and recovery,there are various pros and cons on each method we follow.As a DBA we may need to determine the best and most efficient way for backup and in worst scenarios recovery methodologies.

When saying this we use RMAN in our environment for backups.
The backup scripts are normal RMAN backup commands which are fired against Oracle Database 10g(10.2.0.3).

We noticed that after the backup was completed the RMAN prompt would never come.
It took nearly 2hours to come to a RMAN prompt.

We thought it was problem in the Media management layer and some believed that the tape drive was really slow.

On research found that the TEMP tablespace was also utilised to huge extent and most of the time TEMP tablespace would blow up.

The workaround would be to perform the following :-

server50 $ rman / target catalog rman/rman@catalog
RMAN > sql "alter session set optimizer_mode=RULE";

Run the above sql in the RMAN prompt and then perform normal RMAN operations.