DB2 for z/OS: Data Sharing in a Nutshell

DB2 for z/OS: Data Sharing in a Nutshell

by Paolo Bruni, Mark Anders, KyengDong Park, Mark Rader, Judy Ruby-Brown
Released October 2006
Publisher(s): IBM Redbooks
ISBN: None

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Book description

DB2 for z/OS takes advantage of data sharing technology in a z Parallel Sysplex to provide applications with full concurrent read and write access to shared DB2 data. Data sharing allows users on multiple DB2 subsystems, members of a data sharing group, to share a single copy of the DB2 catalog, directory, and user data sets.

Data sharing provides improvements to availability and capacity without impacting existing applications.
The road to data sharing might seem arduous to a novice user, but once you have started to learn terminology and gain basic understanding, things will become much easier.

This IBM Redbooks publication is meant to facilitate your journey towards data sharing by providing a cookbook approach to the main tasks in enabling data sharing and workload balancing. It does not have all the answers, because it is a brief summary of a large field of knowledge, but it contains the key elements and it points you in the right direction to get more details. Throughout this document we assume that your sysplex environment is set up and a DB2 subsystem exists at a currently supported level.

Table of contents

  1. Notices
    1. Trademarks
  2. Preface
    1. Our assumptions
    2. The team that wrote this redbook
    3. Become a published author
    4. Comments welcome
  3. Chapter 1: Introduction
    1. Why should you implement DB2 data sharing?
    2. Overview of Parallel Sysplex and DB2 data sharing
    3. Business value of data sharing
      1. Improved data availability
      2. Extended processing capacity
      3. Configuration flexibility
      4. Higher transaction rates
      5. Application interface unchanged
    4. Roadmap to implementing data sharing
  4. Chapter 2: Data sharing architecture
    1. Parallel database architecture alternatives
    2. Data sharing design for scalability
      1. Global locking and the lock structure
      2. Managing changed data and group buffer pools
    3. Data sharing design for continuous availability (1/2)
    4. Data sharing design for continuous availability (2/2)
    5. Configuration flexibility and systems management
    6. Application considerations in data sharing
      1. Portability
      2. Commit and lock avoidance
      3. Concurrency
  5. Chapter 3: The coupling facility
    1. Structure sizing
      1. Group buffer pools
      2. Sizing the lock structure
      3. Sizing the SCA structure
    2. Auto Alter
      1. Implementing Auto Alter
    3. Duplexing
      1. Group buffer pools (GBP) or user-managed pools
      2. System-managed duplexing
    4. CF configuration alternatives
      1. ICF-only: Double failure for the lock and SCA structures
      2. System-managed duplexing for DB2 lock and other structures
      3. External CF, such as z890 or z9 BC
    5. CFRM policy
    6. Best practices for the coupling facility
  6. Chapter 4: Implementing data sharing
    1. Naming conventions
      1. Group name
      2. Group attachment name
      3. Subsystem identifier (SSID)
      4. Log data set names
      5. Bootstrap data set (BSDS)
      6. Distributed Data Facility (DDF) related parameters
      7. Catalog alias
      8. Temporary work file database
      9. Some more naming recommendations
      10. Examples of naming conventions
      11. Best practices for naming conventions
    2. Logging
      1. Active log data sets
      2. Archive log
      3. Best practices for DB2 logging
    3. DSNZPARMs
      1. Data sharing system parameters
      2. Some other important DSNZPARMs
      3. IRLM parameters
      4. Information stored in the BSDS
    4. Renaming an existing non-data sharing member
      1. IPL required for these tasks
      2. Enable data sharing tasks
    5. Enabling the data sharing group
      1. Additional tasks
    6. Adding the second member
    7. Removing a member
  7. Chapter 5: Dynamic workload balancing
    1. Objectives of workload balancing
    2. Workload Manager
    3. Dynamic virtual IP addressing (DVIPA)
    4. Sysplex Distributor
    5. Distributed data facility (DDF)
    6. Stored procedures
    7. Batch work
    8. WebSphere
    9. CICSPlex Systems Manager (CP/SM)
    10. IMS Transaction Manager (IMS TM)
    11. Dynamic workload balancing best practices
  8. Chapter 6: Operations
    1. Recovery of DB2 objects
      1. Log record sequence number (LSRN)
      2. Group buffer pool recovery pending (GRECP)
      3. Logical page list (LPL)
      4. Recommendations for GRECP/LPL recovery
      5. Best practices for GRECP/LPL recovery
    2. Component failure
      1. DB2 subsystem failure
      2. z/OS system failure
      3. CF failure
    3. Sysplex failure management (SFM) policy
    4. Automatic restart manager (ARM)
    5. Restart Light
      1. Best practices for failures
    6. Commands
      1. Basics
      2. CF and structure related commands
      3. IRLM commands
      4. DB2 commands
    7. Multi-system DB2 diagnostic dumps
    8. Disaster recovery
    9. Rolling maintenance
      1. Service recommendations
      2. Best practices for maintenance
  9. Chapter 7: Advanced topics
    1. CLOSE YES and CLOSE NO table spaces
      1. Best practice
    2. Performance
    3. Eliminating false contention
    4. How many CF engines are necessary?
    5. Lock avoidance: CLSN versus GCLSN
    6. The problem of runaway threads
    7. Usermod for routing to multiple DB2s on a z/OS image
      1. Multiple DB2 members in one z/OS image
    8. Determining the number of threads
      1. REXX tools package
      2. Statistics Spreadsheet support
  10. Chapter 8: Best practices
    1. Table of best practice recommendations
  11. Related publications
    1. IBM Redbooks
    2. Other publications
    3. Online resources
    4. How to get IBM Redbooks
    5. Help from IBM
  12. Index (1/2)
  13. Index (2/2)
  14. Back cover

Product information

  • Title: DB2 for z/OS: Data Sharing in a Nutshell
  • Author(s): Paolo Bruni, Mark Anders, KyengDong Park, Mark Rader, Judy Ruby-Brown
  • Release date: October 2006
  • Publisher(s): IBM Redbooks
  • ISBN: None