Which of the following is true about multiple DBWn processes? (Choose three.)
A. Configured by setting the DB_WRITER_PROCESSES initialization parameter to a value greater than 1 and less than or equal to 10.
B. The processes are named DBW0 through DBW9.
C. They can improve dirty buffer write performance on multiprocessor systems.
D . The processes are named DBW1 through DBW10.
E . The number of processes is dynamically configurable by the DBA.
Explanation:
Answer A, B and C: The DB_WRITER_PROCESSES, default value 1, and values 1 through 10 set the number of DBW processes. If 1, then only the DBW0 process will be used. The valid processes are DBW0 through DBW9. Multiple DBW processes can reduce write contention due to the DBW0 process being overworked. The number of processes is set in the init.ora parameter and is not dynamically configurable, or automatically adjusted.
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