What is the result of increasing the value of the parameter ASM_POWER_LIMIT during a
rebalance operation?
A.
The ASM rebalance operation will likely consume fewer resources and complete in a
shorter amount of time.
B.
The ASM rebalance operation will consume fewer resources and complete in a longer
amount of time.
C.
The ASM rebalance operation will be parallelized and should complete in a shorter
amount of time.
D.
There is no ASM_POWER_LIMIT setting used in ASM.
E.
None of the above
E is correct when question is asked in such a way. Increasing the value of the parameter ASM_POWER_LIMIT during a rebalance operation will alter the power limit for any new operations, but not existing ones. To change an existing operation, you must directly alter the power limit on the diskgroup involved in the operation.
ASM_POWER_LIMIT is a dynamic parameter, which also can be set with alter system command while rebalance operation is already going on. Hence option C is correct. Ofcourse it all depends upon the resources available, but point here is the parameter can be changed dynamically and it will impact ongoing rebalance operation to speedup.
The answer is E
To alter the POWER there are 2 possibilities
SQL> alter system set asm_power_limit=11; — alteres the power limit for any new operations, but not existing ones.
Checking v$asm_operation will show you that currently running rebalances will not run faster.
The power level of an existing/ongoing rebalance operation can be changed by entering the rebalance statement with a new (power) level on the diskgroup involved in the operation:
SQL> alter diskgroup dgroup1 rebalance power 11;
Checking v$asm_operation will show this to be the case.
Note: The power can be set from the start in the add/drop statement with the following syntax:
SQL> alter diskgroup dgroup1 drop disk vol005 rebalance power 11;