Oracle9i Real Application Clusters Concepts Release 2 (9.2) March 2002 Part No. A96597-01 Oracle9i Real Application Clusters Concepts, Release 2 (9.2) Part No. A96597-01 Copyright © 1998, 2002 Oracle Corporation. All rights reserved. Primary Author: Mark Bauer. Contributors: David Austin, Wilson Chan, Sashikanth Chandraserkaran, Jonathan Creighton, Lisa Eldridge, Mitch Flatland, Rick Greenwald, Eugene Ho, Bill Kehoe, Raj Kumar, Kotaro Ono, Stefan Pommerenk, Rebecca Reitmeyer, Joao Rimoli, Daniel Semler, Vinay Srihari, Alok Srivastava, Tak Wang, Shari Yamaguchi, and Tolga Yurek. Graphic Designer: Valarie Moore. The Programs (which include both the software and documentation) contain proprietary information of Oracle Corporation; they are provided under a license agreement containing restrictions on use and disclosure and are also protected by copyright, patent and other intellectual and industrial property laws. 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Contents List of TablesFigures Send Us Your Comments ................................................................................................................. xiii Preface........................................................................................................................................................... xv What’s New in Real Application Clusters?........................................................................... xxv Part I Cluster Database Processing Fundamentals 1 Introduction to Real Application Clusters What Is Real Application Clusters? ................................................................................................ 1-2 The Benefits of Real Application Clusters..................................................................................... 1-3 Lower Overall Cost of Ownership............................................................................................. 1-3 Expanded Scalability.................................................................................................................... 1-3 High Availability .......................................................................................................................... 1-4 Transparency................................................................................................................................. 1-4 Buffer Cache Management.......................................................................................................... 1-4 Row Locking.................................................................................................................................. 1-5 Multiversion Read Consistency.................................................................................................. 1-5 Recovery Manager, Online Backups, and Archiving .............................................................. 1-5 2 Real Application Clusters Systems Architecture Overview of Cluster Database System Components................................................................... 2-2 Nodes and Their Components.................................................................................................... 2-3 Cluster Interconnect and Interprocess Communication (Node-to-Node) ........................... 2-3 iii Memory, Interconnect, and Storage................................................................................................. 2-4 The High-Speed IPC Interconnect................................................................................................... 2-4 Shared Disk Storage and the Cluster File System Advantage................................................... 2-4 3 Real Application Clusters Software Architecture The Operating System-Dependent Clusterware .......................................................................... 3-2 The Cluster Manager.................................................................................................................... 3-2 The Node Monitor ........................................................................................................................ 3-2 The Interconnect............................................................................................................................ 3-3 Real Application Clusters Shared Disk Components ................................................................. 3-3 Real Application Clusters-Specific Daemon and Instance Processes....................................... 3-3 The Global Services Daemon ...................................................................................................... 3-4 Instance Processes Specific to Real Application Clusters ....................................................... 3-4 The Global Cache and Global Enqueue Service........................................................................... 3-6 Application Transparency........................................................................................................... 3-6 Global Resource Directory with Distributed Architecture..................................................... 3-6 Resource Mastering and Affinity ............................................................................................... 3-7 GCS and GES Interaction with the Cluster Manager .............................................................. 3-7 4 Scalability in Real Application Clusters Scalability Features of Real Application Clusters........................................................................ 4-2 All System Types Benefit from Real Application Clusters......................................................... 4-2 Transaction Systems and Real Application Clusters............................................................... 4-2 Data Warehouse Systems and Real Application Clusters ...................................................... 4-3 Levels of Scalability ........................................................................................................................... 4-3 Network Scalability ...................................................................................................................... 4-4 Network Scalability and Client/Server Connectivity ............................................................. 4-4 Operating System Scalability ...................................................................................................... 4-6 Part II Resource Coordination in Real Application Clusters 5 Real Application Clusters Resource Coordination Overview of Real Application Clusters Resource Coordination............................................... 5-2 The Contents of the Global Resource Directory....................................................................... 5-2 Real Application Clusters Synchronization Processes ............................................................ 5-3 Enqueues........................................................................................................................................ 5-3 iv Past Images.................................................................................................................................... 5-3 Resource Modes and Roles ............................................................................................................... 5-4 Resource Modes............................................................................................................................ 5-4 Resource Roles .............................................................................................................................