for class on Tuesday Oct. 22, 1996
Please re-read Sections 2.6 through 2.9 of the Patterson & Hennessy text, together with the Web material mentioned below, and be prepared to discuss the following:
The Standard Performance Evaluation Corporation (a.k.a. SPEC) is a group of computer manufacturers that agree on a set of standard benchmarks and on measurement methods for evaluating their machines. Execution times are compared with the times on a ``reference machine,'' which is now a certain SPARC workstation. Before this organization was formed (in the late 1980's) competing companies often used different benchmarks to tout their machines, and/or suspicious figures of merit like MIPS (not the company, the metric) and/or questionable ways of combining a set of benchmark numbers.
Please visit the SPEC Website, http://www.specbench.org, and prowl around a little. On the SPEC Results Index page, study the SPECint95 results for at least three different machines, one of which should be a MIPS-architecture SGI workstation. For help in interpreting these dense 1-page summaries, see the Example Report Page and the SPEC CPU95 Q&A page. Other links at this site may also be helpful; just look around. Learn how to interpret these reports; a great deal of information is included in each. Bear in mind that these are measurements of systems containing these processor chips; different systems with the same chip might have different performance, due to differences in non-CPU elements.
What does it mean to say that one computer is faster than another?