The system includes Easy Tier, which is a function that responds to the presence of drives in a storage pool that also contains hard disk drives (HDDs). The system automatically and nondisruptively moves frequently accessed data from HDD MDisks to flash drive MDisks, thus placing such data in a faster tier of storage.
Easy Tier eliminates manual intervention when you assign highly active data on volumes to faster responding storage. In this dynamically tiered environment, data movement is seamless to the host application regardless of the storage tier in which the data belongs. However, you can manually change the default behavior. For example, you can turn off Easy Tier on pools that have any combination of the four types of MDisks.
All MDisks belong to one of the tiers, which includes MDisks that are not yet part of a pool.
If a pool contains one type of MDisk, Easy Tier goes into balancing mode. When the pool contains multiple types of MDisks, Easy Tier is automatically turned on.The local MDisks are classified as tier 0 flash, tier 1 flash, enterprise, or nearline drives. The system supports both tier 0 and tier 1 flash drives. Tier 0 flash drives are higher-cost flash drives that provide high performance for read and write operations. Tier 1 flash drives are lower-cost flash drives that have large capacity but lower performance and write endurance characteristics.