Database Journal
MS SQL Oracle DB2 Access MySQL PostgreSQL Sybase PHP SQL Etc SQL Scripts & Samples Tips Database Forum Rss Feed

» Database Journal Home
» Database Articles
» Database Tutorials
MS Access
SQL Scripts & Samples
» Database Forum
» Slideshows
Free Newsletters:

News Via RSS Feed

Rss Feed

Database Journal |DBA Support |SQLCourse |SQLCourse2

Featured Database Articles


Posted May 30, 2008

Oracle Database 11g: Database Replay, Part 2 - Page 3

By Jim Czuprynski

Phase 3: Replaying the Workload

Since my target database has now been reset to its prior state just before workload capture was initiated and all my P+1 changes are now in place, at last I’m ready to initiate the replay of the workload. I’ll use EM Database Control to initiate the replay, as shown in Figure 2.4.1 below.

Click for larger image

Figure 2.4.1: Workload Replay: Starting Point

Once I’ve selected a directory that already contains a captured workload, Oracle 11g makes sure that I’ve reviewed all required prerequisites for a successful replay, including what external references (e.g. external files and directories) need to be resolved before proceeding, as shown in Figures 2.4.2 and 2.4.3 below.

Figure 2.4.2: Workload Replay: Confirming Prerequisites

Figure 2.4.3: Workload Replay: Confirming References to External Systems

Once all prerequisites have been confirmed, it’s time to set up the actual EM task that will perform the replay. Figure 2.4.4 shows how I set up the basics for this task ...

Figure 2.4.4: Workload Replay: Setting Up Replay Task

... and Figure 2.4.5 shows how I remapped the current connection strings generated during the initial workload capture so that the identical connection strings are used during this database replay operation.

Figure 2.4.5: Workload Replay: Setting Up Connection Strings

As I described in the Database Replay primer article, Oracle 11g allows me to alter the frequency at which a workload is played back with extreme granularity. To keep this demonstration simple, I’ve accepted the default options shown in Figure 2.4.6.

Figure 2.4.6: Workload Replay: Customizing Replay Options

It’s now almost time to start the Workload Replay Client (WRC) to play back the previously captured workload. As Figure 2.4.7 illustrates, my next step is to start the WRC with the appropriate parameters and then return to this screen and select the Next button to initiate the workload’s automatic replay:

Figure 2.4.7: Workload Replay: Initiating Workload Replay Clients

I’ll start the replay session by opening a terminal session and invoking the WRC client executable. Note that I first changed my present working directory to /home/oracle/DBRControl before starting up the WRC:

$>  wrc system/oracle@orcl mode=replay replaydir=.
Workload Replay Client: Release - Production on Thu May 22 19:28:59 2008
Copyright (c) 1982, 2007, Oracle.  All rights reserved.
Wait for the replay to start (19:28:59)

Returning to EM Database Control, I simply click on the Next button, and Oracle 11g acknowledges that it has taken control of any active database replay operations ...

Figure 2.4.8: Workload Replay: Controlling Replay Operations

... and that’s also reflected from within the terminal sessions themselves.

Wait for the replay to start (19:28:59)
Replay started (19:31:17)

Back at EM Database Control, the status of the database replay operation is constantly being monitored ...

Figure 2.4.9: Workload Replay: Monitoring Active Replay Operations

..; until the replay operation is completed.

Wait for the replay to start (19:28:59)
Replay started (19:31:17)
Replay finished (19:37:02)

Figure 2.4.10: Workload Replay: Completed Replay Operation

Oracle Archives

Latest Forum Threads
Oracle Forum
Topic By Replies Updated
Oracle Data Mining: Classification jan.hasller 0 July 5th, 07:19 AM
Find duplicates - Unique IDs Lava 5 July 2nd, 08:30 AM
no matching unique or primary key rcanter 1 April 25th, 12:32 PM
Update values of one table based on condition of values in other table using Trigger Gladiator 3 February 29th, 06:01 PM