Experiences from Applying WCET Analysis in Industrial Settings
Jan Gustafsson, Andreas Ermedahl · 2007
Knowing the program timing characteristics is funda-mental to the successful design and execution of real-time systems. Today, measurement-based timing analysis tools such as in-circuit emulators, logic analyzers and oscillo-scopes, are used in industry. A critical timing measure is the worst-case execution time (WCET) of a program. Re-cently, tools for deriving WCET estimates, mostly based on static program analysis, have reached the market. In this article we summarize experiences from five differ-ent industrial case-studies. The studies were made on typi-cal industrial systems, in close cooperation with the system developers, using both static and measurement-based tools. The primary purpose was to investigate the difficulties in-volved in applying current timing analysis methods to in-dustrial code. We were also interested howWCET estimates can be derived by different methods, how labor-intensive the methods are, and the accuracy of obtained results. As a result, we provide observations on the benefits and drawbacks of the different timing analysis methods used and specify general conditions when a particular method should be most beneficial. We also show the benefits of having sev-eral types of timing analysis tools available. 1