Data center: SSD or HDD?

The amount of information that data centers are storing and accessing is on the rise, especially with the increasing popularity of multimedia content. Enterprises are faced with new challenges with regard to storage and access of this data and are on a constant lookout for new solutions to manage complexity, retention, indefinite scaling of storage capacity, etc.

One of the changes large enterprises are retorting to on an enterprise level is solid state drives (SSD) in their data centers in place of hard disk drives (HDD). It can often get confusing which one is best for your data center. The critical question is when is SSD a better solution for you than an HDD.

Difference between HDD and SSD

The main difference lies in the method each uses for storing data. According to Storage Review, SSD can be thought of as an oversized and more sophisticated version of the humble USB memory stick. Like a memory stick, there are no moving parts to an SSD, information is stored in microchips. Meanwhile, a hard drive uses a mechanical arm with a read/write head to move around and read information from the right location on a storage platter. This difference is what makes SSD so much faster - because HDD requires more mechanical movement to get information.

Advantages of SSD

Firstly, they are faster. SSDs can read and write data at rates of around 200-500MB/s (typically, writing is slower than reading), compared with only 50-120MB/s for their HDD brethren. Judy Bruner, CFO and executive VP of Administration at SanDisk Corporation says, "SSDs give you much faster access to your data or applications on the data center. CIOs see a great advantage in this when they use high-performance applications as it tends to speed up storage network and applications. Faster access to big data When it comes to design, SSDs are much slimmer and more rugged in nature. It doesn't vibrate and make noise like HDD. Moreover, SSD uses much lesser battery as it relies on silicon rather than mechanical operation, and are hence cooler than HDD driven data centers". This also means better battery life, and you spend lesser cost and energy on data center cooling. Moreover, SSDs don't have fragmentation problems, unlike HDDs. The next obvious question is why are HDDs still around.

Advantages of HDD

HDDs score high in price and storage capacity. SSDs have become steadily cheaper, with price per GB declining by 50% every 18 months, a Deloitte study states. However, HDD prices have declined even faster in the past three decades at a rate of 50% every 14 months. SSDs are roughly 10 times more expensive per bit than HDDs at present. The other major factor that hurts SSDs is capacity. SSDs offer numerous advantages over HDDs, but it cannot compete in terms of inexpensive mass storage capacity and cost.

A balance

This brings us to the core of the topic - which one should you choose. If one has a good budget and don't mind limited storage capacity, SSD is the way to go. Else, a hybrid approach is the most appealing implementation in data centers. Hybrid storage systems can be implemented to overcome the disadvantages of each technology. Data centers can use expensive SSDs where faster read and write or booting is required. Meanwhile it can include inexpensive HDDs where large storage is needed since these drives offer much cheaper and more capacious storage. In the data center, look for a balance-rather than dominance by one or the other-of these technologies.