A description is given of a novel design, using a hierarchy of controllers, that effectively controls a multiuser, multiprogrammed parallel system. Such a structure allows dynamic repartitioning according to changing ...
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A description is given of a novel design, using a hierarchy of controllers, that effectively controls a multiuser, multiprogrammed parallel system. Such a structure allows dynamic repartitioning according to changing job requirements. The design goals are examined, and the principles of distributed hierarchical control are presented. Control over processors is discussed. Mapping and load balancing with distributed hierarchical control are considered. Support for gang scheduling as well as availability and fault tolerance is addressed. The use of distributed hierarchical control in memory management and I/O is discussed
Given a positive integer M, and a set S = {x(1),x(2),...,x(n),) of positive integers, the maximum subset sum problem is to find a subset S' of S such that Sigma(x is an element of S') x is maximized under the ...
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Given a positive integer M, and a set S = {x(1),x(2),...,x(n),) of positive integers, the maximum subset sum problem is to find a subset S' of S such that Sigma(x is an element of S') x is maximized under the constraint that the summation is no larger than M. In addition, the cardinality of S' is also a maximum among all subsets of S which achieve the maximum subset sum. This problem is known to be NP-hard. We analyse the average-case performance of a simple on-line approximation algorithm assuming that all integers in S are independent and have the same probability distribution. We develop a general methodology, i.e., using recurrence relations, to evaluate the expected values of the content and the cardinality of S' for any distribution. The maximum subset sum problem has important applications, especially in static job scheduling in multiprogammed parallelsystems. The algorithm studied can also be easily adapted for dynamic job scheduling in such systems. (C) 1998 Elsevier Science Ltd. All rights reserved.
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