156.What is the effect of increasing the value of the ASM_POWER_LIMIT parameter?
A. The number of DBWR processes increases
B. The number of ASMB processes increases
C. The number of DBWR_TO_SLAVES increases
D. The rebalancing operation in an ASM instance completes more quickly, but can result in higher I/O
overhead
Answer: D
答案解析：
参考：http://blog.csdn.net/rlhua/article/details/12972983
ASM_POWER_LIMIT
The ASM_POWER_LIMIT initialization
parameter specifies the default power for disk rebalancing in a disk group. The range of values is 0 to 1024. The default value is 1. A value of 0 disables rebalancing. Higher numeric values enable the rebalancing
operation to complete more quickly, but might result in higher I/O overhead and more rebalancing processes.
-
For disk groups that have the disk group ASM compatibility set to
11.2.0.2or greater (for example,COMPATIBLE.ASM=11.2.0.2), the operational range of values is0to1024for the rebalance power. -
For disk groups that have the disk group ASM compatibility set to less than
11.2.0.2, the operational range of values is0to11inclusive. If the value forASM_POWER_LIMITis larger than11, a value of11is used for these disk groups.
You can also specify the power of the rebalancing operation in a disk group with the POWER clause of the SQL ALTER DISKGROUP ... REBALANCE statement. The range of allowable values
for the POWER clause is the same for the ASM_POWER_LIMIT initialization parameter. If the value of the POWER clause is specified larger than 11 for a disk group with ASM compatibility set to less than 11.2.0.2,
then a warning is displayed and a POWER value equal to 11 is used for rebalancing.