1 说明
Oracle ASM rebalance enhancements improve scalability, performance, and reliability of the rebalance operation. This feature extends the rebalance to operate on multiple disk groups in a single instance. In addition, it improves support for thin provisioning, user data validation, and improved error handling.
With this new feature, you can distribute the rebalance load for higher performance, obtain better user validation, and control error handling and support for thin provisioning.
在12c中，Oracle ASM rebalance增强提高了rebalance操作的可伸缩性、性能和可靠性。Oracle对底层的代码和锁机制进行了重新优化。
另外可以通过对操作的EXPLAIN，然后查询v$asm_estimate视图来查看预估的时间。
如：
SQL > EXPLAIN WORK FOR ALTER DISKGROUP DATA ADD DISK ‘/dev/asmdiskb’ power 5;
SQL > Select est_work from v$asm_estimate;
EST_WORK
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23 --单位:分钟