JESSICA: Java-Enabled Single-System-Image Computing Architecture

Abstract

JESSICA stands for Java-enabled single-system-image computing architecture, a middleware that runs on top of the standard UNIX operating system to support parallel execution of multithreaded Java applications in a cluster of computers. JESSICA hides the physical boundaries between machines and makes the cluster appear as a single computer to applications - a single system image. JESSICA supports preemptive thread migration, which allows a thread to freely move between machines during its execution, and global object sharing through the help of a distributed shared-memory subsystem. JESSICA implements location-transparency through a message-redirection mechanism. The result is a parallel execution environment where threads are automatically redistributed across the cluster for achieving the maximal possible parallelism. A JESSICA prototype that runs on a Linux cluster has been implemented and considerable speedups have been obtained for all the experimental applications tested. © 2000 Academic Press.