Enhancing the usage of the Shared Class Cache
University of New Brunswick
With the increasing popularity of the Java language and sandboxed environments, research needs to be conducted into improving the performance of these environments by decreasing the execution time as well as the memory footprint of an application. This thesis examines various critical data structures, used by IBM's Java Virtual Machine (JVM) during the start-up phase, for potential improvements. These data structures start small and expand as required in order to save space, however, growing them slows down the start-up of the JVM. This thesis will describe how the data structures were optimized using the Shared Class Cache (SCC), in order to improve the execution time as well as the memory footprint of the application running on IBM's JVM. The impact of this approach on performance and memory has been evaluated using different benchmarks. On average, a performance increase of 6% and a memory reduction of about 1% has been achieved with this approach. The alterations made are completely automated and the user requires no prior knowledge about the Java application or the VM to improve the performance of the deployed application. The only task the user has, is to activate the SCC.