Solid state disk revolution looms

We've all experienced it: that sense of frustration whenever the disk drive LED on your laptop turns solid green for a seemingly interminable period. While enduring one such interruption recently, my thoughts turned longingly to solid state drives and their emergence as a force to be reckoned with both at the low end and high. Several recent news items underscore this fact.

The benefits in laptop designs are obvious -- longer battery uptime, increased reliability, better performance - but the cost of a good-sized SSD is nearly the same as the laptop itself. Intel and Micron's joint announcement concerning 32 gigabit NAND chips should be viewed as good news for those of us anxiously awaiting an affordable drive.

While most of the SSD attention has centered on the low end of the market and the impact on portable devices, disk drive giant Seagate's announcement that it will offer SSDs next year targets the enterprise. This announcement quickly followed its patent infringement lawsuit against SSD vendor STEC, and, as some have pointed out, provides additional evidence of the future threat that SSDs are likely to pose to traditional hard disk drives (HDDs).

STEC, by the way, is the company that supplies solid state storage for enterprise-class DMX storage systems from EMC, who recently had an announcement of its own, indicating aggressive plans to promote enterprise SSDs and to drive the price point near to traditional hard disk drive levels. Specifically targeted were high-end 15,000 RPM fibre channel disks -- a high-margin cash cow for HDD makers.

With a claimed performance advantage of up to 30:1 for enterprise-class SSDs, it's easy to envision in the near future a tiered storage architecture consisting of SSDs at the high end and various combinations of Fibre Channel, SAS, or SATA storage at the middle and low tiers.

Beyond cost, the most often cited concerns regarding SSDs relate to performance and endurance. The first generation of low-end SSDs offers what appears to be only marginally better performance than HDDs. While throughput differences are not that great, latency is significantly better, and newer drive controllers provide optimizations that promise performance improvements up to several orders of magnitude.

Endurance, or longevity, is also dramatically increasing as next generation controllers feature advanced static and dynamic wear leveling algorithms. By redistributing writes across the entire drive and clever handling of frequently updated blocks, SSD life can be extended many years.

So, whether you're trying to multitask on your laptop (like listening to music while writing a column, maybe) or you're designing a high I/O transaction storage architecture, it's becoming increasingly likely that solid state storage will play a role in your future.

Jim Damoulakis is chief technology officer of GlassHouse Technologies Inc., a leading provider of independent storage services. He can be reached at jimd@glasshouse.com.