These vendors all provide some type of automated tiering system. Many of them are based on storage federation or virtualization.
Compellent pioneered the technology in 2005 with its Data Progression for NAS and SAN. Its Storage Center 5, announced in January, provides daily, block-level retiering based on data usage patterns, as well as support for SSD and RAID 6 configurations. It remains the market leader, says Forrester analyst Andrew Reichman, because of its automation and ability to retier data units smaller than LUNs. However, he says, it doesn’t offer the performance and reliability that larger customers need.
FalconStor Software Inc. has long offered a technology called HotZone for automated, block-based caching of data for read-intensive processes and another called SafeCache for write-intensive operations. Later this year, it plans to add file tiering and an intelligent ILM engine that can automatically retier data based on various criteria, such as age or access rate, as well as capabilities such as support for thin provisioning and de-duplication, says Fadi Albatal, FalconStor’s vice president of marketing.
NAS appliances from Avere Systems offer block-level, real-time automated retiering of storage based on historic and predictive analysis of data usage. That includes which groups of blocks are accessed together, and whether the access is random or sequential. Avere appliances can also automatically retier data based on the attributes of new storage types as they’re added to the system, such as SSDs, which read data faster than they write.
3PAR Inc. recently added Policy Advisor, which provides array-based analysis of factors such as capacity utilization and required performance, to its Dynamic Optimization software, which seamlessly moves data between tiers. Because “users demand some control,” it offers recommendations, rather than automatic retiering of data, when applications approach customer-defined performance thresholds, says Craig Nunes, vice president of marketing. Dynamic Optimization currently operates only at the volume level, but he says the company plans to “address the need for subvolume tiering later this year.”
EMC’s FAST, announced for all of the vendor’s primary arrays late last year, continually analyzes read and write patterns and provides wizard-driven suggestions for retiering, says Bob Wambach, senior director of product marketing. Most retiering is currently done in batch mode, he says, but it can be done in real time when “people get comfortable with the technology.” FAST currently operates only at the volume or LUN level, but sub-LUN tiering is expected in the second half of this year.
F5 Networks Inc.’s ARX series of file virtualization appliances automate retiering of files based on criteria such as age, file type or last access. They don’t require the modification of clients or applications, and they support storage devices from any vendor. However, customers must still create the policies governing file movement, says Renny Shen, product marketing manager for F5’s data solutions division.
