By itself, flash removes the part of the latency bottleneck caused by slow spinning disk drives, but it does nothing to resolve the delay in getting process-critical data to and from the CPU.

Storing data in a flash array puts process-critical data on the wrong side of the storage channel, far away from the CPU that is processing application and database requests.

The result is a minimal performance gain and, in addition to adding more hardware, organizations must also implement complex and costly storage area network infrastructure, including host bus adapters, switches and monolithic arrays.

But most importantly, these architectures retain the traditional implementations of storage, as well as , and controllers -- all optimized to spinning drives, not NAND flash silicon. Figure 2 shows the layers still present in this legacy approach.