052-203(新增70题2018)

Your database performance has degraded due to frequent checkpointing.

What would you do in this scenario?

A. make redo log files smaller

B. increase the size of the checkpoint file

C. make the changes as per the advice given by MTTR Advisor

D. make the changes as per the advice given by Checkpoint Advisor

Answer: C
10.5.3 Tuning FAST_START_MTTR_TARGET and Using MTTR Advisor

  The FAST_START_MTTR_TARGET initialization parameter causes the database to calculate internal system trigger values, in order to limit the length of the redo log and the number of dirty data buffers in the data cache. This calculation uses estimated time to read a redo block, estimates of the time to read and write a data block and characteristics of typical workload of the system, such as how many dirty buffers corresponds to how many change vectors, and so on.
  After you have selected a preliminary value for FAST_START_MTTR_TARGET, you can use MTTR Advisor to evaluate the effect of different FAST_START_MTTR_TARGET settings on system performance, compared to your chosen setting.
  

mean time to recover (MTTR)

The time required to perform recovery.

原文地址:https://www.cnblogs.com/Babylon/p/8601782.html