This old-fashioned, predictable storage I/O path was deterministic and decipherable: The server, the switch, and the array all had enough information to do their jobs effectively and efficiently.
I/O blender
The Four Horsemen of Storage System Performance: Get Smart
The Four Horsemen of storage system performance cannot be denied, but they do offer a clear path forward. Storage systems must improve in many different areas, from spindles and drives to caching and I/O bottlenecks. But above all else, storage systems must become smarter in order to become faster, and this requires greater insight into the true nature of the data stream being stored. All storage performance developments, from the laptop to the enterprise, boiled down to adaptations to the demands of the Four Horsemen.