You notice that the performance of the database has degraded because of frequent
checkpoints. Which two actions resolve the issue? (Choose two.)
A.
Check the size of the redo log file size and increase the size if it is small
B.
Set the FAST_START_MTTR_TARGET parameter as per the advice given by the MTTR
Advisor
C.
Decrease the number of redo log members if there are more than one redo l og members
available in each redo log group
D.
Disable automatic checkpoint tuning
a,b
a,b
http://docs.oracle.com/database/121/TGDBA/pfgrf_build_db.htm#TGDBA94147
The size of the redo log files can influence performance, because the behavior of the database writer and archiver processes depend on the redo log sizes. Generally, larger redo log files provide better performance. Undersized log files increase checkpoint activity and reduce performance.
Although the size of the redo log files does not affect LGWR performance, it can affect DBWR and checkpoint behavior. Checkpoint frequency is affected by several factors, including log file size and the setting of the FAST_START_MTTR_TARGET initialization parameter. If the FAST_START_MTTR_TARGET parameter is set to limit the instance recovery time, Oracle Database automatically tries to checkpoint as frequently as necessary. Under this condition, the size of the log files should be large enough to avoid additional checkpointing due to under sized log files. The optimal size can be obtained by querying the OPTIMAL_LOGFILE_SIZE column from the V$INSTANCE_RECOVERY view. You can also obtain sizing advice on the Redo Log Groups page of Oracle Enterprise Manager.