SSD Poised To Move Into The Data Center

Very high costs versus very dramatic performance improvements. Those are the two items that enterprises will have to balance as Solid State Disk (SSD) encroaches upon hard disk storage in the data center. Currently, the number of SSD products available is limited both by availability and their high price tags. Despite those obstacles, a number of companies have forged ahead and are deploying with SSD systems, which, though far from perfect, are proving to be intriguing.

SSD may seem like a recent phenomenon, but enterprises have used them for about 25 years. Their initial niche was as cache in real-time, performance hungry applications or in military and industrial applications, where the working environment was too harsh for standard magnetic hard disks. While those areas continue to be soft land spots for SSD, it has been working its way into the storage mainstream. Companies, like Compellent Technologies, EMC, Fusion-i/o, Hitachi Data Systems, IBM, Intel Corp., NetApp, Seagate, Samsung, Sun Microsystems, and Verari Systems Inc., have delivered or -- more likely -- are building SSD products.

So what is the attraction? Performance. An SSD system provides 20,000 I/O processes compared to 200 for hard disk storage, according to Clod Barrera, IBM's chief technical strategist for Storage. Many enterprises now need the performance boost. "With the growing use of dual-, quad-, and multi-core processors, there are applications where performance requirements are outstripping the capabilities of traditional HDDs," said Jeff Janukowicz, research manager at International Data Corp. Solid state has the potential to enable companies to deploy new applications or to dramatically improve the performance of their existing systems.  Early customers have been reporting response times plummeting by averages of 50 percent to more than 100 percent.
    
Another benefit is the systems consume very little power. As IT departments' data requirements have grown, so have their energy bills. Consequently, they have been pressuring vendors to make their products more energy efficient. Because SSDs hold information in memory, they do not perform as many reads and writes as hard disk storage. Because of the potential benefits, the SSD market is growing at a rapid rate. Gartner found that in 2009 vendors shipped 280,000 SSD units accounting for $450 million in revenue and expects those numbers to increase to 5.3 million units and $1.9 billion in 2013.

While flash has many benefits, it also presents companies with a few challenges. The main issue is its price. Hard disk drives cost around 20 cents to 50 cents per gigabyte, while solid-state drives cost $2 to $4 per gigabyte. So, the cost of a single 15K 300 GB Fibre Channel hard disk drive would be about $2,000 while a comparable SSD would run about $20,000 to $25,000.

Because the disk is so expensive, it does not make sense for companies to deploy SSD across their entire storage architecture. "Flash is emerging as a compliment rather than a full replacement for hard disk storage," noted Joseph Unsworth, research director at Gartner. Corporations are using it to front end their data, and the term "Tier 0" is being used to describe SSD's place in a company's storage hierarchy.As a result, corporations must tinker with their arrays to take advantage of the potential performance boost. That process requires monitoring their information flows, placing the data that is updated most frequently in flash, and leaving the rest in hard disk. Right now, the tools that could help them do that in an intelligent manner are either non-existent or in an early stage of development. In addition, applications and operating systems may need to be revamped in order for companies to fully maximize flash's potential.

Another issue is reliability. SSDs have emerged from the consumer market, where the workload and reliability requirements are low compared to those with enterprise systems. The new drives wear out faster than HDD drives, which creates a couple of problems. First, companies need sophisticated management tools that will be proactive and take steps to ensure that a drive problem will not knock all of their applications offline.  Also, the additional maintenance requirements may possibly increase a firm's manpower requirements and hardware costs.

Long term, vendors are expected to address SSD's limitations. So, the question for enterprises now is: Do they want to evaluate the tradeoffs or wait a while until vendors address a few of the initial kinks?