Summary: An Analysis of Operating System Behavior on a
Simultaneous Multithreaded Architecture
Joshua A. Redstone, Susan J. Eggers and Henry M. Levy
University of Washington
{redstone, eggers, levy}@cs.washington.edu
Abstract
This paper presents the first analysis of operating system execution
on a simultaneous multithreaded (SMT) processor. While SMT has
been studied extensively over the past 6 years, previous research
has focused entirely on user­mode execution. However, many of
the applications most amenable to multithreading technologies
spend a significant fraction of their time in kernel code. A full
understanding of the behavior of such workloads therefore requires
execution and measurement of the operating system, as well as the
application itself.
To carry out this study, we (1) modified the Digital Unix 4.0d
operating system to run on an SMT CPU, and (2) integrated our
SMT Alpha instruction set simulator into the SimOS simulator to
provide an execution environment. For an OS­intensive workload,
we ran the multithreaded Apache Web server on an 8­context

Source: Anderson, Richard - Department of Computer Science and Engineering, University of Washington at Seattle

Collections: Computer Technologies and Information Sciences