SDI Seminar

Speaker: Dr. Sharon Perl, Systems Research Center, Digital Equipment Corp.

On-line Performance Monitoring

Date: March 27, 1995

Abstract: ``Performance assertion checking'' is an approach to automating the testing of performance properties of complex systems. System designers write assertions that capture expectations for performance; these assertions are checked automatically against monitoring data to detect potential performance bugs. Automatically checking expectations allows a designer to test a wide range of performance properties as a system evolves: data that meets expectations can be discarded automatically, focusing attention on data indicating potential problems.

PSpec is a language for writing performance assertions together with tools for testing assertions and estimating values for constants in assertions. The language is small and efficiently checkable, yet capable of expressing a wide variety of performance properties. An initial report on PSpec appears in the Proceedings of the December 1993 Symposium on Operating Systems Principles.

In this talk I will describe the PSpec language and approach, and also talk about our latest work on tools for continuous monitoring using PSpec. The CMon tools provide the ability to continuously or periodically extract performance data from long-running programs and to check performance expectations for programs during normal use. They decouple the user of a program from the experimenter who is interested in studying the program's performance, and are thereby helpful for performance studies of non-long-running programs as well.

This is joint work with Prof. Bill Weihl of MIT, currently on leave at DEC SRC