What is AWR Report in Oracle 10g?

Automatic Workload Repository (AWR) in Oracle Database 10g

Oracle have provided many performance gathering and reporting tools over the years. Originally the UTLBSTAT/UTLESTAT scripts were used to monitor performance metrics. Oracle8i introduced the Statspack functionality which Oracle9i extended. In Oracle 10g statspack has evolved into the Automatic Workload Repository (AWR).

AWR Features

The AWR is used to collect performance statistics including:

• Wait events used to identify performance problems.
• Time model statistics indicating the amount of DB time associated with a process from the V$SESS_TIME_MODEL and V$SYS_TIME_MODEL views.
• Active Session History (ASH) statistics from the V$ACTIVE_SESSION_HISTORY view.
• Some system and session statistics from the V$SYSSTAT and V$SESSTAT views.
• Object usage statistics.
• Resource intensive SQL statements.

The repository is a source of information for several other Oracle 10g features including:

• Automatic Database Diagnostic Monitor
• SQL Tuning Advisor
• Undo Advisor
• Segment Advisora