%T Native JCSP \- the CSP for Java library with a Low\-Overhead CSP Kernel
%A  James Moores
%E Peter H. Welch,  Andr\[`e] W. P. Bakkers
%B Communicating Process Architectures 2000
%X The JCSP library provides a superior framework for building
   concurrent Java applications. Currently, CSP is a collection
   of classes that uses the standard Java Threads mechanism to
   provide low\-level facilities such a process scheduling and
   synchronization. The overheads of using Java Threads can be
   quite large though, especially for synchronization and
   context switching. This paper begins by describing various
   options for increasing performance, and then how the
   standard Java threads work. The integration of the
   low\-overhead CCSP run\-time system into a Linux\-based Sun
   JDK 1.2.1 Java Virtual Machine is then described. This
   integration provides the low\-level support required to
   dramatically increase the performance of the JCSP
   library\[rs]s model of concurrency. The paper then looks at
   the problem of maintaining backward compatibility by
   preserving the functionality of the existing threads
   mechanism on which much legacy code depends. The paper
   finishes by looking at the performance displayed by the
   current prototype JVM and contrasting it with the
   performance of both Green (co\-operatively scheduled) and
   Native (operating\-system scheduled) Java Threads.