Placement of replicated items in distributed databases
We address the problem of determining an allocation scheme for replicated data in a distributed database, with the purpose of minimizing required communication. An allocation scheme establishes the number of copies of each data-item, and at which processors of a given computer network the copies should be located. The problem for general networks is shown NP-Complete, but we provide efficient algorithms to obtain an optimal allocation scheme for three common types of network topologies. They are completely-connected, tree, and ring networks. We also propose a new method by which a processor in a computer network should write all the copies of a replicated data item. This method leads to surprising results concerning the allocation schemes.
KeywordsSpan Tree Allocation Scheme Communication Cost Steiner Tree Connected Subgraph
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- [C]R. G. Casey, "Allocation of Copies of a File in an Information Network", Proc. 1972 Spring Joint Computer Conference, AFIPS, 1972.Google Scholar
- [CMP]S. Ceri, G. Martella, and G. Pelagatti, "Optimal File Allocation in a Computer Network: a Solution Method Based on the Knapsack Problem", Computer Networks, 6:5, 1982.Google Scholar
- [DF]L. W. Dowdy and D. V. Foster, "Comparative Models of the File Assignment Problem", ACM Computing Surveys, 14:2, 1982.Google Scholar
- [IK]K. B. Irani and N. G. Khabbaz, "A Methodology for the Design of Communication Networks and the Distribution of Data in Distributed Supercomputer Systems", IEEE Transactions on Computers, C-31:5, 1982.Google Scholar
- [M]A. Milo, M. Sc. Thesis, The Technion — IIT, Jan. 1988.Google Scholar
- [ML]H. L. Morgan and J. D. Levin "Optimal Program and Data Location in Computer Networks", Communications of the ACM, 20:5, 1977.Google Scholar
- [MR]S. Mahmoud and J. S. Riordon, "Optimal Allocation of Resources in Distributed Information Network", ACM-TODS, 1:1, 1976.Google Scholar
- [SW]A. Segall and O. Wolfson, "Transaction Commitment at Minimal Communication Cost", Proc. 6th ACM Symp on Principles of Database Systems, 1987.Google Scholar
- [Z]B. Zelinka, "Medians and Peripherians on Trees", Arch. Math. (Brno), 1968.Google Scholar