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 11.2.0.2 or higher (for example, COMPATIBLE.ASM = 11.2.0.2), the operational range of values is 0 to 1024 for 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 is 0 to 11 inclusive. If the value for ASM_POWER_LIMIT is larger than 11, a value of 11 is 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.
The specification of the power of the rebalancing operation in a disk group only affects rebalance operations, not new allocations to a disk group.
For information about the ASM_POWER_LIMIT initialization parameter, and the POWER clause, refer to "Manually Rebalancing Disk Groups" and "Tuning Rebalance Operations". For information about disk group compatibility, see "Disk Group Compatibility".
Oracle Database Reference for more information about the ASM_POWER_LIMIT initialization parameter
Oracle Database SQL Language Reference for more information about the POWER clause of the SQL ALTER DISKGROUP REBALANCE statement