Storage tiering is nothing new but then again is all new. Traditionally, tiering meant that you’d buy fast (Tier One) storage arrays, based on 15K Fibre Channel drives, for your really important applications. Next you’d buy some slower (Tier Two) storage arrays, based on SATA drives, for your not-so-important applications. Finally you’d buy a (Tier Three) tape library or VTL to house your backups. This is how most people have accomplished storage tiering for the past couple of decades, with slight variations. For instance I’ve talked to some companies that had as many as six tiers when they added their remote offices and disaster recovery sites – these were very large users with very large storage requirements who could justify breaking the main three tiers into sub-tiers.
Whether you categorized your storage into three or six tiers, the basic definition of a tier has historically been a collection of storage silos with particular cost and performance attributes that made them appropriate for certain workloads. Recent developments, however, have changed this age-old paradigm:
1) The post-recession economy has driven IT organizations to look for ways to cut costs by improving storage utilization
2) The introduction of the SSD offers intriguing performance but a higher cost than most can afford
3) Evolving storage array intelligence now automates the placement of “hot” data without human intervention
These three events lead to a rebirth of sorts in tiering, in the form of Automated Storage Tiering. This style of tiering allows the use of new components like SSD without breaking the bank. Assuming that for any given workload, a small percentage of data is accessed very frequently, Automated tiering allows the use of high performance components for that data only, while the less-frequently accessed data can be automatically stored on more economical media.
As with any new technology, or in this case a new technique, vendors are approaching automated tiering from different angles. This is good for consumers in the long run (the best implementations will eventually win out) but in the short run creates some confusion when determining which vendor you should align you and your data with.
As a result, automated storage tiering is getting quite a bit of press from vendors and industry analysts alike. For example, here are two pieces that appeared recently:
Information Week Storage Virtualization Tour – All About Automated Tiering
Business Week – Auto Tiering Crucial to Storage Efficiency
SNIA is also interested in helping clear any confusion around automated storage tiering. This week the DPCO committee will host a live webcast panel of tiering vendors to discuss the pros and cons of tiering within the scope of their products, you can register for it here: Sign up
Join this session and learn more about similarities and differences in various tiering implementations. We hope to see some “lively” interaction, so join the tiering discussion and get your questions answered.
See you there!
Larry
PS – If you can’t make this week’s Webcast, we’ll also be recording it and you’ll be able to view it from the DPCO website