Using Schema Remapping

This section describes how to use schema remapping with Consolidated Database Replay, and assumes a scenario where you want to use schema remapping to identify possible host bottlenecks when deploying multiple instances of an application. The scenario demonstrates how to use schema remapping for scale-up testing. For more information about schema remapping, see "About Schema Remapping".

This scenario uses the following assumptions:

• A single workload exists that is captured from the Sales application.

• To set up the replay system with multiple schemas from the Sales schema, schema remapping is performed by adding the captured workload multiple times into a replay schedule and remapping the users to different schemas.

To perform schema remapping in this scenario:

1. On the replay system where you plan to perform scale-up testing, create a directory object for the root directory where the captured workloads are stored:

   CREATE OR REPLACE DIRECTORY cons_dir AS '/u01/test/cons_dir';
   

2. Create a directory object for the directory where the captured workload is stored:

   CREATE OR REPLACE DIRECTORY cap_sales AS '/u01/test/cons_dir/cap_sales';
   

   Ensure that the captured workload from the Sales application is stored in this directory.

3. Preprocess the captured workload:

   EXEC DBMS_WORKLOAD_REPLAY.PROCESS_CAPTURE ('CAP_SALES');
   

4. Set the replay directory to the root directory:

   EXEC DBMS_WORKLOAD_REPLAY.SET_REPLAY_DIRECTORY ('CONS_DIR');
   

5. Create a replay schedule and add the captured workload multiple times:

   EXEC DBMS_WORKLOAD_REPLAY.BEGIN_REPLAY_SCHEDULE ('double_sales_schedule');
   SELECT DBMS_WORKLOAD_REPLAY.ADD_CAPTURE ('CAP_SALES') FROM dual;
   SELECT DBMS_WORKLOAD_REPLAY.ADD_CAPTURE ('CAP_SALES') FROM dual;
   EXEC DBMS_WORKLOAD_REPLAY.END_REPLAY_SCHEDULE;
   

6. Initialize the consolidated replay:

   EXEC DBMS_WORKLOAD_REPLAY.INITIALIZE_CONSOLIDATED_REPLAY (
                             'double_sales_replay', 'double_sales_schedule);
   

7. Remap the users:

   EXEC DBMS_WORKLOAD_REPLAY.SET_USER_MAPPING (2, 'sales_usr', 'sales_usr_2');
   

8. Prepare the consolidated replay:

   EXEC DBMS_WORKLOAD_REPLAY.PREPARE_CONSOLIDATED_REPLAY;
   

9. Start replay clients:

   1. Estimate the number of replay clients that are required:

      wrc mode=calibrate replaydir=/u01/test/cons_dir/cap_sales
      

   2. Add the output to determine the number of replay clients required.

      You will need to start at least one replay client per workload capture contained in the consolidated workload.

   3. Start the required number of replay clients by repeating this command:

      wrc username/password mode=replay replaydir=/u01/test/cons_dir
      

      The replaydir parameter is set to the root directory in which the workload captures are stored.

10. Start the consolidated replay:

    EXEC DBMS_WORKLOAD_REPLAY.START_CONSOLIDATED_REPLAY;