Oracle Performance Tuning – How to Use AWR ?

Here are few silver bullets to use AWR for diagnosing performance issues ….. AWR – Automatic Workload Repository Detailed & comprehensive performance history Based on “snapshot” (time interval) Automatic Database Diagnostic Monitor (ADDM) About 79 DBA_HIST_* “tables” Defaults: Hourly snapshots Weekly retention (month is better) Overview of important AWR tables DBA_HIST_SNAPSHOT PK: SNAP_ID DBID, INSTANCE_NUMBER […]

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Understand each sections of AWR

AWR report is broken into multiple parts. 1)Instance information:- This provides information the instance name , number,snapshot ids,total time the report was taken for and the database time during this elapsed time. Elapsed time= end snapshot time – start snapshot time Database time= Work done by database during this much elapsed time( CPU and I/o […]

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