Four considerations for SSD deployment

While solid state drives offer increased performance, the key to figuring out the role they can play in the data center is balancing that performance against cost.

SSD technology has been around for decades and has become more popular in laptops and desktops, especially among power users clamoring for the biggest performance bang for the buck. The word has spread and businesses are recognizing the advantages of using SSD in the data center to turbo-charge mission-critical applications. Companies can typically use fewer SSDs compared to the number of traditional spinning disks they would have to deploy to achieve equivalent performance.

However, not all solid state technology is built the same. The speed of SSDs doesn't come cheap; the average price per gigabyte is approximately 10 times more than traditional disks. Before adopting SSDs, you need to understand what is driving your performance needs and which SSD configuration is most appropriate for your applications.

Here are four hardware and software considerations for SSDs:

1. The need for speed: Are SSDs the answer?

In its study, "Worldwide Solid State Drive 2007-2012 Forecast and Analysis: Entering the No-Spin Zone," IDC forecasts the market for SSDs will grow 70% between 2007 and 2012, but adoption of this new storage infrastructure will not happen overnight.

SSD provides the power to significantly increase IOPS for the most demanding applications. It also frees up overtaxed traditional drives in tiered storage environments to function at maximum ability. Tiered storage moves data between high-performance, low-capacity drives and slower, higher-capacity drives. However, integrating SSDs into an environment not optimized for the technology can be a lot like fitting a square peg into a round hole.

To balance speed and cost, you should start small without having to purchase a lot of SSDs up front. Make sure you can maximize storage utilization of SSDs by combining the drives with key virtualization applications. See if you can integrate the technology in your existing array or if you need to install another "brick" or array to use SSD. Without the right infrastructure, the drives can quickly become too costly, difficult to manage and inefficient compared with traditional spinning media. When you're evaluating SSDs check with your vendor candidates to determine how SSDs can be integrated into their existing system and how to maximize functionality.

2. Drive vs. cache: Two ways to configure SSD

Once you decide to implement SSDs you must consider the actual configuration. The primary (and much debated) choices for maximizing efficiency are whether you implement the drives as cache or persistent storage.

Cache-based configurations can improve the performance of a server or controller by acting like additional DRAM memory. Many controllers are essentially closed systems and won't accept cache cards, so the only option is to add a dedicated SSD cache, but that approach tends to be costly. Controllers that accept cache cards do so at the expense of a valuable PCI express slot, which would otherwise be used to maximize the number of ports. However, the biggest drawback to implementing SSDs as cache is that it prevents users from tiering storage, which many in the industry believe is the most efficient path to SSD utilization and performance.