A File System All Its Own: Flash memory has come a long way. Now it’s time for software to catch up.

In the past five years, flash memory has progressed from a promising accelerator, whose place in the data center was still uncertain, to an established enterprise component for storing performance-critical data. It’s rise to prominence followed its proliferation in the consumer world and the volume economics that followed (see figure 1). With SSDs (solid-state devices), flash arrived in a form optimized for compatibility - just replace a hard drive with an SSD for radically better performance. But the properties of the NAND flash memory used by SSDs differ significantly from those of the magnetic media in the hard drives they often displace. While SSDs have become more pervasive in a variety of uses, the industry has only just started to design storage systems that embrace the nuances of flash memory. As it escapes the confines of compatibility, significant improvements in performance, reliability, and cost are possible.