Process management mechanisms (process duplication, migration and checkpoint/restart) are very useful for high performance and high availability in clustering systems. The single system image approach aims at providing a global process management service with mechanisms for process checkpoint, process migration and process duplication. In this context, a common mechanism for process virtualization is highly desirable but traditional operating systems do not provide such a mecahnism.

This paper presents a kernel service for process virtualization called ghost process, extending the Linux kernel. The ghost process mechanism has been implemented in the Kerrighed single system image based on Linux.