<XML><RECORDS><RECORD><REFERENCE_TYPE>1</REFERENCE_TYPE><REFNUM>7169</REFNUM><AUTHORS><AUTHOR>Dickman,P.W.</AUTHOR></AUTHORS><YEAR>1992</YEAR><TITLE>Distributed Object Management in a Non-Small Graph of Autonomous Networks with Few Failures (PhD)</TITLE><PLACE_PUBLISHED>PhD dissertation, University of Cambridge Computer Laboratory</PLACE_PUBLISHED><PUBLISHER>N/A</PUBLISHER><LABEL>Dickman:1992:7169</LABEL><ABSTRACT>The increasing availability of high-performance networks, and the associated demand for distributed applications software, particularly multi-media systems, poses a significant challenge to systems developers. One effective way to manage complexity in such distributed programs is to use object-based techniques, and this, in turn, generates a need for distributed object-support systems. This dissertation addresses a three-way tension in such systems, attempting to reconcile: administrative autonomy; collaborative working across organizational boundaries; and the scale of modern communications networks. A simpel architectural framework, supporting autonomous establishments engaged in co-operative projects, is presented and within this context scalable distributed object management mechanisms are investigated. In p[articular, two new mechanisms are developed. A hybrid distributed garbage detection system is produced that is efficient within establishments and which scales to arbitrarily large systems, provided that the size of individual projects and establishments is limited. The core of the garbage detector is an optimised wighted reference counting mechanism taht efficiently and rapidly recovers acyclic distributed garbage. A system-level load balancer is also introduced, this uses an unusual clump detection heuristic to eliminate gross imbalances in load. Novel features of this mechanism include: the use of multiple load measures; dynamically varying buddy sets selected in a non-uniform random fashion; and clumps of interacting objects as the basic unit of load balancing.</ABSTRACT></RECORD></RECORDS></XML>