A hybrid monitor for behavior and performance analysis of distributed systems

The authors describe a hybrid monitor for measuring the performance and observing the behavior of distributed systems during execution. They emphasize data collection, analysis and presentation of execution data. A special hardware support, which consists of a test and measurement processor (TMP), was designed and has been implemented in the nodes of experimental multicomputer system consisting of eleven nodes. The operations of the TMP are completely transparent with a minimal, less than 0.1%, overhead to the measured system. In the experimental system, all the TMPs were connected with a central monitoring station, using an independent communication network, in order to provide a global view of the monitored system. The central monitoring station displayed the resulting information in easy-to-read charts and graphs. Experience with the TMP shows that it promotes an improved understanding of run-time behavior and performance measurements, which aids in deriving qualitative and quantitative assessments of distributed systems