Explanation:
If you set a value for the FAST_START_MTTR_TARGET too low DBWR will write the data blocks more frequently to reduce recovery time in accordance with the FAST_START_MTTR_TARGET parameter. It can cause the overall database performance degradation. Incorrect Answer:
2: It will not make LGWR to write redo blocks more frequently: data blocks will be written more frequently by DBWR.
3: You don’t need to substantially increase the size of your database buffer cache to hold the additional checkpoint records.
4: You don’t need to substantially increase the size of your redo buffer cache to hold the additional checkpoint records.
Reference:
OCP Oracle 9i Database: New Features for Administrators, Daniel Benjamin, p. 42-45
Chapter 2: Availability Enhancements
Oracle 9i New Features, Robert Freeman, p. 73-75
Chapter 3: New Oracle 9i Availability and Recoverability Features

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