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Stochastic Petri net analysis of a replicated file systemA stochastic Petri-net model of a replicated file system is presented for a distributed environment where replicated files reside on different hosts and a voting algorithm is used to maintain consistency. Witnesses, which simply record the status of the file but contain no data, can be used in addition to or in place of files to reduce overhead. A model sufficiently detailed to include file status (current or out-of-date), as well as failure and repair of hosts where copies or witnesses reside, is presented. The number of copies and witnesses is a parameter of the model. Two different majority protocols are examined, one where a majority of all copies and witnesses is necessary to form a quorum, and the other where only a majority of the copies and witnesses on operational hosts is needed. The latter, known as adaptive voting, is shown to increase file availability in most cases.
Document ID
19890044720
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Bechta Dugan, Joanne (Duke University Durham, NC, United States)
Ciardo, Gianfranco (Software Productivity Consortium Herndon, VA, United States)
Date Acquired
August 14, 2013
Publication Date
April 1, 1989
Publication Information
Publication: IEEE Transactions on Software Engineering
Volume: 15
ISSN: 0098-5589
Subject Category
CYBERNETICS
Funding Number(s)
CONTRACT_GRANT: AF-AFOSR-84-0132
CONTRACT_GRANT: NAG1-70
Distribution Limits
Public
Copyright
Other