Real Application Testing - Database Replay

Applies to:
Oracle Server - Enterprise Edition - Version: 10.1.0.2 and later [Release: 10.1 and later ]

Goal
To give a basic introduction to workload capture and replay

Solution
What is the workload capture/replay utility

Prior to 11G it was extremely difficult to test what effects any upgrades may have on workloads without great expense. Customers want to
see some confidence in any changes they may make to configuration before they go ahead an go production on any new implementations.
Some keys changes which would typically require proper testing are:-

o Hardware/Software Upgrades
o Implementation of new features

Using this new utility it is easy to confidentally predict the outcome of any changes on a given workload. Typically what would happenis that a typical workload (for instance a period of OLTP activity or a batch job) will be recorded with the 'capture' utility and then passed to a copy of the instance which has been upgraded and the workload replayed. Using existing features like AWR it is then easy to compare
the effect of any changes which have been made and then put into place corrective actions should that be required.

The workload capture/replay utility works by us being able to record the workload in the RDBMS and then replaying that workload by havingclients (WRC processes) consume the recorded information and replaying that to the RDBMS, so the replay is actually controlled from outside the database rather then inside it.

Before you begin

1) The Real Application Testing Option must be installed
2) The package dbms_workload_capture must be present and valid (created by dbmswrr.sql as part of the install)

Restrictions

The following will not be captured during a workload capture :-

o Direct path load of external files
o Shared Server requests
o Streams
o Advanced Replication streams
o Non PL/SQL AQ
o Flashback queries
o OCI based object navigations
o Non SQL based object access
o Distributed transactions
o Remote describe/commit operations

Steps:

Programmatic Method:


-Thanks