While the transfer rate results were limited by our Areca controller, it is obvious that to determine the transfer speed of a RAID 0 array, you can almost add the maximum transfer speed of all the hard drives and subtract some 10-15% overhead on controllers optimized for throughput. While the conventional drives will lose performance once you start filling them up, flash SSDs will always maintain their bandwidth.
However, throughput isn’t the most important aspect for enterprise hard drives. In fact, large enterprises often rely on maximum transaction and I/O performance for their servers. Think of banks, Web service providers, and other server-bound applications.
While the hardware environment opposes the main bottleneck for complex RAID configurations, especially RAID 6 and RAID 5, the flash SSDs were able to increasingly show their muscles with less complex array types. I/O performance in RAID 0 is between 5x and 20x faster on MemoRight flash SSDs than on Seagate Cheetah 15K.5 drives. In RAID 5 and RAID 6, the performance benefit is still between 50% more and several times more I/O operations per second.
ROI Great for Enterprises
Obviously, MemoRight flash SSDs are still a rather expensive affair at roughly $1,800 for the 64 GB model we received for this review. Compared to about $150 for the 73 GB version of the Cheetah 15K.5, this equals 12 times the cost. Is this really worth it?
For enterprises looking for maximum transaction performance, an investment of $10,000 to $20,000 will be worthwhile if transaction and business processes are accelerated. In the end, a 4x to 20x improvement in I/O performance hasn’t happened with conventional hard drives in the past, and it never will happen.
Other Customers, Hold Your Fire
Everyone else should hold off on enterprise SSD investments unless there is a specific business case demanding it—for example, a database server for a high-traffic website. Consider that if you can buy a single server and three or four Flash SSDs instead of eight to 12 hard drives spread between two servers, the flash SSDs might more cost effective, while still providing better I/O performance.
Our results make it very obvious that the era of conventional enterprise hard drives will come to an end within the next few years. Lower cost, higher capacity drives will take over the segment, and flash-based hard drives will overrun the enterprise space, starting at the high-end and making their way down to the business mainstream as prices decline.