Enforcing quality of service of distributed objects

Three algorithms designed to enforce different quality of service criteria are presented, as well as empirical assessments of the algorithms for three large industrial telecommunications systems. These assessments are made in terms of the simulated performance of each system on average loads selected from operational distributions collected during beta release and field use. In addition, synthetic heavy loads designed to cause the overall CPU utilization rates to exceed 90% of capacity were run. The algorithms build on previously defined load testing algorithms, and use parameters and operational distributions computed for that purpose. This makes the quality of service enforcement algorithms particularly efficient. The primary bases for the assessment of the algorithms were the overall deviation of the response time from the average, and the fraction of service requests that were throttled from clients under varying conditions.