Babylon: A Java-based distributed object environment.

摘要

This thesis reports on the building of a system in Java, designed to handle distributed objects. A fully functional prototype system, named Babylon, has been built which implements the infrastructure to support distributed Java objects. By leveraging the security and portability features of Java, Babylon allows interested parties to contribute heterogeneous hardware resources to a shared computing system, without concern for security. While other Java-based distributed systems exist, we believe Babylon represents an improvement over other systems because of the combination of features supported by Babylon.; Babylon is composed of class libraries which are written entirely in Java and that run on any standard compliant Java virtual machine. These class libraries implement and combine several key features that are essential to supporting distributed and parallel computing using Java. Such features include the ability to: (1) easily create objects, which require no special programming, on remote hosts and interact with those objects through either synchronous or asynchronous remote method invocations, (2) freely migrate objects to heterogeneous hosts at any point in time, (3) request console, file or socket input and/or output on the originating host, regardless of the location of the object, (4) seamlessly handle the arrivals and departures of compute servers to and from the system.; We report on a system comprised of class libraries, which enables programmers to easily interface both new and pre-existing objects with independent Babylon server objects, which manage the physical resources available to complete the computation. Experimental results are included which demonstrate the overheads involved in each feature. Drawing from these results, and from experience using Babylon, we conclude with a discussion of Babylon's strengths and weaknesses.