RATS: Resource Aware Thread Scheduling for JVM level Clustering

In this work, we propose RATS, a middleware to enhance and extend the Terracotta framework for Java with the ability to transparently execute multi-threaded Java applications to provide a singlesystem image. It supports efficient scheduling of threads, according to available resources, across several nodes in a Terracotta cluster, taking advantage of the extra computational and memory resources available. It also supports profiling to gather application characteristics such as dispersion of thread workload, thread interarrival time and resource usage of the application. It uses bytecode instrumentations to profile and add clustering capabilities to multi-threaded Java applications, as well as extra synchronization if needed. We developed a range of alternative scheduling heuristics and classify them based on the application and cluster behavior. The middleware is tested with a cpu-intensive application with varying thread characteristics to assess and classify the scheduling heuristics with respect to application speed-ups and load balancing.