Performance study of protocols in replicated database.

by Ching-Ting, Ng.Thesis (M.Phil.)--Chinese University of Hong Kong, 1996.Includes bibliographical references (leaves 79-82).Abstract --- p.iAcknowledgement --- p.iiiChapter 1 --- Introduction --- p.1Chapter 2 --- Background --- p.5Chapter 2.1 --- Protocols tackling site failure --- p.5Chapter 2.2 --- Protocols tackling Partition Failure --- p.6Chapter 2.2.1 --- Primary site --- p.6Chapter 2.2.2 --- Quorum Consensus Protocol --- p.7Chapter 2.2.3 --- Missing Writes --- p.10Chapter 2.2.4 --- Virtual Partition Protocol --- p.11Chapter 2.3 --- Protocols to enhance the Performance of Updating --- p.11Chapter 2.3.1 --- Independent Updates and Incremental Agreement in Replicated Databases --- p.12Chapter 2.3.2 --- A Transaction Replication Scheme for a Replicated Database with Node Autonomy --- p.13Chapter 3 --- Transaction Replication Scheme --- p.17Chapter 3.1 --- A TRS for a Replicated Database with Node Autonomy --- p.17Chapter 3.1.1 --- Example --- p.17Chapter 3.1.2 --- Problem --- p.18Chapter 3.1.3 --- Network Model --- p.18Chapter 3.1.4 --- Transaction and Data Model --- p.19Chapter 3.1.5 --- Histories and One-Copy Serializability --- p.20Chapter 3.1.6 --- Transaction Broadcasting Scheme --- p.21Chapter 3.1.7 --- Local Transactions --- p.22Chapter 3.1.8 --- Public Transactions --- p.23Chapter 3.1.9 --- A Conservative Timestamping Algorithm --- p.24Chapter 3.1.10 --- Decentralized Two-Phase Commit --- p.25Chapter 3.1.11 --- Partition Failures --- p.27Chapter 4 --- Simulation Model --- p.29Chapter 4.1 --- Simulation Model --- p.29Chapter 4.1.1 --- Model Design --- p.29Chapter 4.2 --- Implement at ion --- p.37Chapter 4.2.1 --- Simulation --- p.37Chapter 4.2.2 --- Simulation Language --- p.37Chapter 5 --- Performance Results and Analysis --- p.39Chapter 5.1 --- Simulation Results and Data Analysis --- p.39Chapter 5.1.1 --- Experiment 1 : Variation of TRS Period --- p.44Chapter 5.1.2 --- Experiment 2 : Variation of Clock Synchronization --- p.47Chapter 5.1.3 --- Experiment 3 : Variation of Ratio of Local to Public Transaction --- p.49Chapter 5.1.4 --- Experiment 4 : Variation of Number of Operations --- p.51Chapter 5.1.5 --- Experiment 5 : Variation of Message Transmit Delay --- p.55Chapter 5.1.6 --- Experiment 6 : Variation of the Interarrival Time of Transactions --- p.58Chapter 5.1.7 --- Experiment 7 : Variation of Operation CPU cost --- p.61Chapter 5.1.8 --- Experiment 8 : Variation of Disk I/O time --- p.64Chapter 5.1.9 --- Experiment 9 : Variation of Cache Hit Ratio --- p.66Chapter 5.1.10 --- Experiment 10 : Variation of Number of Data Access --- p.68Chapter 5.1.11 --- Experiment 11 : Variation of Read Operation Ratio --- p.70Chapter 5.1.12 --- Experiment 12 : Variation of One Site Failed --- p.72Chapter 5.1.13 --- Experiment 13 : Variation of Sites Available --- p.74Chapter 6 --- Conclusion --- p.77Bibliography --- p.79Chapter A --- Implementation --- p.83Chapter A.1 --- Assumptions of System Model --- p.83Chapter A.1.1 --- Program Description --- p.83Chapter A.1.2 --- TRS System --- p.85Chapter A. 1.3 --- Common Functional Modules for Majority Quorum and Tree Quo- rum Protocol --- p.88Chapter A.1.4 --- Majority Quorum Consensus Protocol --- p.90Chapter A. 1.5 --- Tree Quorum Protocol --- p.9

Independent Updates and Incremental Agreement in Replicated Databases

. Update propagation and transaction atomicity are major obstacles to the development of replicated databases. Many practical applications, such as automated teller machine networks, flight reservation, and part inventory control, do not require these properties. In this paper we present an approach for incrementally updating a distributed, replicated database without requiring multi-site atomic commit protocols. We prove that the mechanism is correct, as it asymptotically performs all the updates on all the copies. Our approach has two important characteristics: it is progressive, and non-blocking. Progressive means that the transaction's coordinator always commits, possibly together with a group of other sites. The update is later propagated asynchronously to the remaining sites. Non-blocking means that each site can take unilateral decisions at each step of the algorithm. Sites which cannot commit updates are brought to the same final state by means of a reconciliation mechanism. Th..

Independent Updates and Incremental Agreement in Replicated Databases

Update propagation and transaction atomicity are major obstacles to the development of replicated databases. Many practical applications, such as automated teller machine (ATM) networks, flight reservation, and part inventory control, do not really require these properties. In this paper we present an approach for incrementally updating a distributed, replicated database without requiring multi-site atomic commit protocols. We prove that the mechanism is correct, as it asymptotically performs all the updates on all the copies. Our approach has two important characteristics: it is progressive, and non-blocking. Progressive means that the transaction's coordinator always commits, possibly together with a group of other sites. The update is later propagated asynchronously to the remaining sites. Non-blocking means that each site can take unilateral decisions at each step of the algorithm. Sites which cannot commit updates are brought to the same final state by means of a reconciliation me..