Optimistic-Preventive Replication in a Database Cluster

In a database cluster, preventive replication can provide strong consistency without the limitations of synchronous replication. However, the original proposal [11] and its extension to partial replication [3] have performance limitations: to prevent conflicts, transactions are forced to wait a delay time before executing. In this paper, we address this problem in order to scale up to large cluster configurations. Our first contribution is an Optimistic Preventive refreshment algorithm (OptPrev) that reduces delays optimistically and prevents inconsistencies for partially-replicated databases. Our second contribution is an optimization that improves transaction throughput. We describe the implementation of OptPrev in our RepDB* prototype over a cluster of 64 nodes running PostgreSQL. Our experimental results using the TPC-C Benchmark show that our algorithm has excellent scale up and speed up.

[1]  Patrick Valduriez,et al.  Parallel database systems: Open problems and new issues , 1993, Distributed and Parallel Databases.

[2]  Fernando Pedone,et al.  Partial replication in the Database State Machine , 2001, Proceedings IEEE International Symposium on Network Computing and Applications. NCA 2001.

[3]  Sam Toueg,et al.  Fault-tolerant broadcasts and related problems , 1993 .

[4]  Patrick Valduriez,et al.  The RepDB* prototype: Preventive Replication in a Database Cluster , 2004, BDA.

[5]  Patrick Valduriez,et al.  Scaling Up the Preventive Replication of Autonomous Databases in Cluster Systems , 2004, VECPAR.

[6]  Bettina Kemme,et al.  Postgres-R(SI): combining replica control with concurrency control based on snapshot isolation , 2005, 21st International Conference on Data Engineering (ICDE'05).

[7]  Esther Pacitti,et al.  Replica Consistency in Lazy Master Replicated Databases , 2001, Distributed and Parallel Databases.

[8]  Gustavo Alonso,et al.  Don't Be Lazy, Be Consistent: Postgres-R, A New Way to Implement Database Replication , 2000, VLDB.

[9]  Francisco Moura,et al.  Optimistic total order in wide area networks , 2002, 21st IEEE Symposium on Reliable Distributed Systems, 2002. Proceedings..

[10]  Gustavo Alonso,et al.  Ganymed: Scalable Replication for Transactional Web Applications , 2004, Middleware.

[11]  Avishai Wool,et al.  Replication, consistency, and practicality: are these mutually exclusive? , 1998, SIGMOD '98.

[12]  Francois Raab,et al.  TPC-C - The Standard Benchmark for Online transaction Processing (OLTP) , 1993, The Benchmark Handbook.

[13]  Dennis Shasha,et al.  The dangers of replication and a solution , 1996, SIGMOD '96.

[14]  Gustavo Alonso,et al.  Improving the scalability of fault-tolerant database clusters , 2002, Proceedings 22nd International Conference on Distributed Computing Systems.

[15]  Esther Pacitti,et al.  Preventive Multi-master Replication in a Cluster of Autonomous Databases , 2003, Euro-Par.

[16]  Patrick Valduriez,et al.  Principles of Distributed Database Systems , 1990 .

[17]  Patrick Valduriez,et al.  Replicated Databases: concepts, Architectures and Techniques , 1998, Netw. Inf. Syst. J..

[18]  John A. Clark,et al.  Holistic schedulability analysis for distributed hard real-time systems , 1994, Microprocess. Microprogramming.

[19]  André Schiper,et al.  Optimistic Atomic Broadcast , 1998, DISC.