How to Tune the Oracle Database Introducing Automatic Workload Repository

28-4 Developers Guide for Oracle Application Integration Architecture Foundation Pack ■ Oracle Fusion Middleware components – Configuring FMW components for the most optimal performance – Configuring components for concurrency – Configuring logging levels – Configuring Meta Data Service ■ Oracle Web Logic Server The following sections discuss how to configure and tune each of these areas.

28.2 Oracle Database Performance Tuning

This section includes the following topics: ■ Section 28.2.1, How to Tune the Oracle Database ■ Section 28.2.2, Introducing Automatic Workload Repository ■ Section 28.2.3, Configuring Performance Related Database Initialization Parameters ■ Section 28.2.4, Tuning Redo Logs Location and Sizing ■ Section 28.2.5, Automatic Segment-Space Management ASSM ■ Section 28.2.6, Changing the Driver Name to Support XA Drivers ■ Section 28.2.7, Configuring Database Connections and Datasource Statement Caching ■ Section 28.2.8, Oracle Metadata Service MDS Performance Tuning

28.2.1 How to Tune the Oracle Database

The Oracle database that is used as a dehydration data store by SOA Suite must be monitored and tuned to get the best performance from AIA applications. Database administrators must monitor the database for example, by generating Automatic Workload Repository AWR reports for Oracle database to observe lock contention, IO usage and take appropriate action to address the issues.

28.2.2 Introducing Automatic Workload Repository

The Automatic Workload Repository AWR collects, processes, and maintains performance statistics for problem detection and self-tuning purposes. This data is both in memory and stored in the database. The gathered data can be displayed in both reports and views. Oracle generates many types of cumulative statistics for the system, sessions, and individual SQL statements. Oracle also tracks cumulative statistics on segments and services. When analyzing a performance problem in any of these scopes, you typically look at the change in statistics delta value over the period you are interested in. Specifically, you look at the difference between the cumulative value of a statistic at the start of the period and the cumulative value at the end. Cumulative values for statistics are generally available through dynamic performance views, such as the VSESSTAT and VSYSSTAT views. Note that the cumulative values in dynamic views are reset when the database instance is shutdown. Tuning Integration Flows 28-5 The AWR automatically persists the cumulative and delta values for most of the statistics at all levels except the session level. This process is repeated on a regular time period and the result is called an AWR snapshot. The delta values captured by the snapshot represent the changes for each statistic over the time period. AWR supports the capture of baseline data by enabling you to specify and preserve a pair or range of AWR snapshots as a baseline. Carefully consider the time period you choose as a baseline; the baseline should be a good representation of the peak load on the system. In the future, you can compare these baselines with snapshots captured during periods of poor performance. Oracle Enterprise Manager is the recommended tool for viewing both real time data in the dynamic performance views and historical data from the AWR history tables. Enterprise manager can also be used to capture operating system and network statistical data that can be correlated with AWR data. For more information, see Oracle Database 2 Day + Performance Tuning Guide. The statistics collected and processed by AWR include: ■ Object statistics that determine both access and usage statistics of database segments ■ Time model statistics based on time usage for activities, displayed in the VSYS_ TIME_MODEL and VSESS_TIME_MODEL views ■ Some of the system and session statistics collected in the VSYSSTAT and VSESSTAT views ■ SQL statements that are producing the highest load on the system, based on criteria such as elapsed time and CPU time ■ Active Session History ASH statistics, representing the history of recent sessions activity

28.2.3 Configuring Performance Related Database Initialization Parameters