Getting Started with Replicated Berkeley DB Applications

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Table of Contents

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1. Introduction
Replication Environments
Replication Databases
Communications Layer
Selecting a Master
Replication Benefits
Replication Mechanisms
Replication Manager Overview
Write Forwarding Overview
Replication Base API Overview
Holding Elections
Influencing Elections
Winning Elections
Switching Masters
Permanent Message Handling
When Not to Manage Permanent Messages
Managing Permanent Messages
Implementing Permanent Message Handling
Event Handling
2. Transactional Application
Application Overview
Program Listing
Class: RepConfig
Class: SimpleTxn
Method: SimpleTxn.main()
Method: SimpleTxn.init()
Method: SimpleTxn.doloop()
Method: SimpleTxn.printStocks()
3. The DB Replication Manager
Starting and Stopping Replication
Managing Election Policies
Selecting the Number of Threads
Adding the Replication Manager to SimpleTxn
Replication Manager Permanent Message Handling
Identifying Permanent Message Policies
Setting the Permanent Message Timeout
Adding a Permanent Message Policy to RepQuoteExampleGSG
Managing Election Times
Managing Election Timeouts
Managing Election Retry Times
Managing Connection Retries
Managing Heartbeats
4. Replica versus Master Processes
Determining State
Processing Loop
Example Processing Loop
Running It
5. Configuring for Write Forwarding
Application with Write Forwarding Overview
Program Listing
Class: RepWrforConfig
Class: RepQuoteWrforExampleGSG
Method: RepQuoteWrforExampleGSG.main()
Method: RepQuoteWrforExampleGSG.init()
Method: RepQuoteWrforExampleGSG.doloop()
Method: RepQuoteWrforExampleGSG.printStocks()
6. Additional Features
Delayed Synchronization
Managing Blocking Operations
Stop Auto-Initialization
Read-Your-Writes Consistency
Client to Client Transfer
Identifying Peers
Bulk Transfers