Parallel Computer Architecture

142 CHAPTER 3 Programming for Performance

:

First working set

Second working set

Other capacity-independent communication]

Inherent communication

LU

\ \ \\

\

\ \\ \ \ \ u \ \

s

Col^tarUcompulso^

Replication capacity (cache size)

FIGURE 3.6 The data traffic between a cache (replication store) and the rest of

the system and the components of the data traffic as a function of cache size. The

points of inflection in the total traffic curve indicate the working sets of the program.

communication cost can be overlapped with other computation or communication

(all of which are addressed in the orchestration step), and how well the communica-

tion pattern ...