Amber

Developed by:
University of Washington, USA Jeffery S. Chase, Franz G. Amador, Edward D. Lazowska, Henry M. Levy and Richard J. Littlefield

Short Description:
Amber is a programing system that permits a single application program to use a homogeneous network of computers in a uniform way, making the network appear to the application as an integrated multiprocessor. Amber is designed for high performance in the case where each node in the network is shared-memory multiprocessor. Amber shows that support for loosely-coupled multiprocessing can be efficiently realized using an object-based programming model. Amber programs execute in a uniform network-wide object space, with memory coherence maintained at the object level. Careful data replacement and consistency control are essential for reducing communication overhead in a loosely-coupled system. Amber programmers use object migration primitives to control the l ocation of data and processing. Amber is a follow-up to the Emerald project. Amber is implemented on top of the Topaz operating system.

Model: loosely-coupled multiprocessor
Properties: object-oriented, process migration, lightweight processes
Transparency: location, access, concurrency, migration
Running on: DEC Firefly
Date: 1989

References:
Jeffery S. Chase, Franz G. Amador, Edward D. Lazowska, Henry M. Levy and Richard J. Littlefield: "The Amber System: Parallel Programming on a Network of Multiprocessors". Proc. Twelfth ACM Symposium on Operating Systems, Operating Systems Review, Vol. 23, No.5, December 1989, pp.147-158.