-
Book Overview & Buying
-
Table Of Contents
Modern Computer Architecture and Organization - Third Edition
By :
As we learned in previous chapters, each executing process contains one or more threads of execution. When multithreading with time-slicing on a single-core processor, only one thread is in the running state at any given time. By rapidly switching between several ready-to-run threads, the processor creates the illusion (from the user's viewpoint) that multiple programs are running simultaneously.
This chapter introduced the concept of superscalar processing, which enables a single processor core to issue multiple instructions per clock cycle. The performance gains from superscalar execution are reduced when the instruction stream lacks a mix of operations that matches the capabilities of the available functional units. For example, in a particular instruction sequence, integer processing units may be heavily taxed (resulting in pipeline bubbles), while address computation units remain mostly idle.
One way to increase the potential utilization of superscalar...