EMC Announces FAST Upgrades, Including Flash-Based Cache For Clariion, Celerra

EMC is announcing upgrades to its Fully Automated Storage Tiering (FAST) technology, including the use of SSD flash drives for caching, the ability to move blocks of data within a LUN from one tier to another and offering more options for automated data movement. Storage tiering gives administrators the ability to move data among storage media with different performance characteristics. For instance, frequently accessed data that's sitting on SATA drives can be moved to Fibre Channel or SSD flash drives, each of which have faster access times. The upgraded FAST technology will be available in July.

The newest version of FAST will include FAST Cache, which lets administrators use high-performance Flash drives to cache frequently accessed data. EMC says FAST Cache will provide multi-terabyte capacity for read/write operations. Rich Napolitano, President of EMC's Unified Storage Division, claims FAST Cache can reduce response times by as much as 35 percent with file-oriented workloads. FAST Cache will be available in the Clariion CX4 and Celerra NS product lines.

"I like the idea of using Flash as cache," says Howard Marks, chief scientist at DeepStorage.net and a contributing analyst for Network Computing. However, he also notes that competitors such as Compellent already use Flash-based caching. He also notes that there are still questions about how FAST Cache will operate. "Compellent runs a process nightly to look at which blocks have been accessed, and moves them up to Flash, and moves down blocks that have been accessed less recently." Another option is to monitor activity in real time and move data based on changing conditions rather than at a predefined period, but this can burden the SAN. "They didn't say is how reactive the Flash cache is, so there are questions we haven't gotten answers to," says Marks.

The new version of FAST will also let administrators move data among tiers at the sub-LUN level on the Clariion and Celerra platforms. The FAST technology can be configured to automatically move only a segment of data within a LUN to a different storage tier. Previously, the entire LUN would have to be moved to a different tier.

EMC also announced that FAST will give administrators more options for setting tiering policies, including automated data movement based on I/O. Data can be moved to the highest tier (i.e. the best-performing tier) or the lowest tier, so that more space will be available on higher tiers for more frequently accessed data. Finally, the new version of FAST will let administrators use block data compression to squeeze more capacity out of existing disk. Administrators can also choose to compress individual LUNs.