Frank Denneman comments on his blog:
Generic server architecture provides the foundation of the storage controller architecture. These servers are equipped with a bunch of I/O ports. These ports are responsible to establish communication with the back end disks and provide a front-end interface to communicate with the attached hosts. The storage controllers run proprietary software providing data services and specific storage features.
Reviews show that the most popular storage arrays and their storage controller configuration are equipped with two CPUs ranging from four to eight cores. Sure there are some exceptions but lets stick to the most common configurations. This means that the typical enterprise storage array is equipped with 16 to 32 cores in total as they come with two storage controllers. What are these storage controller CPU used for?
A great look at storage controllers from Frank. Read through this carefully and you’ll understand why scale-out storage is so hard to do (and how people are trying to do it).
Read more at: Part 4 – Storage controller architecture