A Dynamic Light Weight Group Service

Luís Rodrigues, Katherine Guo, António Sargento, Robbert van Renesse, Brad Glade, Paulo Veríssimo, Kenneth Birman

Selected sections of this report were published in "A Transparent Light-Weight Group Service", proceedings of the 15th IEEE Symposium on Reliable Distributed Systems, Niagara-on-the-Lake, Canada, October, 1996.


The virtual synchrony model for group communication has proven to be a powerful paradigm for building distributed applications. Implementations of virtual synchrony usually require the use of failure detectors and failure recovery protocols. In applications that require the use of a large number of groups, significant performance gains can be attained if these groups share the resources required to provide virtual synchrony. A service that maps user groups onto instances of a virtually synchronous implementation is called a Light-Weight Group Service.

This paper proposes a new design for the Light-Weight Group protocols that enables the usage of this service in a transparent manner. As a test case, the new design was implemented in the Horus system, although the underlying principles can be applied to other architectures as well. The paper also presents performance results from this implementation.

Also available extended report (gzip postscript), (pdf) .

Additional work

The previous report gives emphasis on the support mechanisms of the architecture and presents performance results for static assignments. We have done additional work on the dynamic aspects of this architecture. You can also check the following paper:
Dynamic Light-Weight Groups.
Katherine Guo and Luís Rodrigues.
Proceedings of the 17th IEEE International Conference on Distributed Computing Systems
Baltimore, Maryland, USA, May, 1997
Available abstract (html) and extended report (gzip postscript).

Luís Rodrigues