Cloneable JVM: a new approach to start isolated java applications faster

Java has been successful particularly for writing applications in the server environment. However, isolation of multiple applications has not been efficiently achieved in Java. Many customers require that their applications are guarded by independent OS processes, but starting a Java application with a new process results in a long sequence of initializations being repeated each time. To date, there has been no way to quickly start a new Java application as an isolated OS process. In this paper, we propose a new isolation approach called Clone-able JVM to eliminate this startup overhead in Java. The key idea is to create a new Java application by copying, or cloning, the already-initialized image of the primary JVM process. Since the clone is already initialized, it can begin actual operations immediately as a new isolated process. This cloning abstraction can support new scenarios for Java, such as user isolation and transaction isolation. We implemented a prototype of the Cloneable JVM by modi-fying a production JVM on Linux, which provides a new API for cloning constructed on the Isolate API defined in JSR 121. Using this cloning API, several Java applications, including a large pro-duction J2EE application server, were modified to demonstrate the isolation scenarios. Evaluations using these prototypes showed that new ready-to-serve Java applications can start up as a new process in less than 5 seconds, which is 4 to 170 times faster than starting these applications from scratch