DB2 10.5 for Linux, UNIX, and Windows

Factors affecting performance

System architecture
Configuring for good performance
Some types of DB2® deployment, such as the InfoSphere® Balanced Warehouse® (BW), or those within SAP systems, have configurations that are highly specified.
Instance configuration
When you start a new DB2 instance, there are a number of steps that you can follow to establish a basic configuration.
Table space design
Database design
Resource utilization
Data organization
Over time, data in your tables can become fragmented, increasing the size of tables and indexes as records become distributed over more and more data pages. This can increase the number of pages that need to be read during query execution. Reorganization of tables and indexes compacts your data, reclaiming wasted space and improving data access.
Application design
Database application design is one of the factors that affect application performance. Review this section for details about application design considerations that can help you to maximize the performance of database applications.
Lock management
Lock management is one of the factors that affect application performance. Review this section for details about lock management considerations that can help you to maximize the performance of database applications.
Explicit hierarchical locking for DB2 pureScale environments
Explicit hierarchical locking (EHL) for IBM® DB2 pureScale® Feature takes advantage of the implicit internal locking hierarchy that exists between table locks, row locks, and page locks. EHL functionality helps avoid most communication and data sharing memory usage for tables.
Query optimization
Query optimization is one of the factors that affect application performance. Review this section for details about query optimization considerations that can help you to maximize the performance of database applications.
Data compression and performance
You can use data compression to reduce the amount of data that must be read from or written to disk, thereby reducing I/O cost.
Reducing logging overhead to improve DML performance
The database manager maintains log files that record all database changes. There are two logging strategies: circular logging and archive logging.
Inline LOBs improve performance
Some applications make extensive use of large objects (LOBs). In many cases, these LOBs are not very large-at most, a few kilobytes in size. The performance of LOB data access can now be improved by placing such LOB data within the formatted rows on data pages instead of in the LOB storage object.