Chapter 10: Improving Performance - TOC

10.2 PERFORMANCE MEASUREMENT

While most well-known tools for measuring performance are stand-alone programs that concentrate on execution speed, there is a comprehensive tool that covers all four aspects of performance. The Ada Compiler Evaluation System (ACES) is the result of merging two earlier products: the United States Department of Defense's Ada Compiler Evaluation Capability and the United Kingdom Ministry of Defence's Ada Evaluation System. It offers a comprehensive set of nearly 2,000 performance tests along with automated setup, test management, and analysis software. This system reports (and statistically analyzes) compilation time, linking time, execution time, and code size. The analysis tools make comparisons among multiple compilation-execution systems and also provide comparisons of the run-time performance of tests using different coding styles to achieve similar purposes.

Version 2.0 of the ACES, released in March of 1995, includes a Quick-Look facility that is meant to replace the Performance Issues Working Group (PIWG) suite. The Quick-Look facility is advertised as being easy to download, install, and execute in less than a day, while providing information that is as useful as that generated by the PIWG suite. In addition, Version 2.0 contains a limited number of Ada 95 tests (all of which are also included in the Quick-Look subset). Version 2.1, including broad coverage of the "core" Ada 95 language, is scheduled for release in March 1996.

At the time of this writing, the ACES software and documentation can be obtained via anonymous FTP from the host sw-eng.falls-church.va.us, directory /public/AdaIC/testing/aces. For World Wide Web access, use the following uniform resource locator (URL): /AdaIC/testing/aces/.

While measuring performance may seem to be a relatively straightforward matter, there are significant issues that must be addressed by any person or toolset planning to do such measurement. For detailed information, see the following sources: ACES (1995a, 1995b, 1995c); Clapp, Mudge, and Roy (1990); Goforth, Collard, and Marquardt (1990); Knight (1990); Newport (1995); and Weidermann (1990).