The I/O Path
Storage data is typically created by an application running on a system processor and then is transferred over the I/O path to its location on storage media. The remainder of this chapter describes the various hardware and software elements that storage data encounters on the I/O path. We'll begin by breaking down the entire end-to-end path and then take a second look at some of the more interesting aspects of host system software elements.
The I/O path can be conceived of as a set of distinct hardware and software elements, each with its own role, that acts on storage data as it moves from point to point along the I/O path.
Table 3-1 shows a generic “top-down” listing of the various hardware and software elements that comprise the ...