ChangeDetector

CA APM ChangeDetector enables Introscope to monitor and report changes in application files and configuration. ChangeDetector detects production web application changes to help you identify when a change is the root cause of an application performance problem. After identifying change as the cause of a problem, you can use ChangeDetector to diagnose the problem. ChangeDetector gives you visibility into changes in code, application server configuration, and the configuration of connected systems that might be responsible for performance issues.
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CA APM ChangeDetector enables Introscope to monitor and report changes in application files and configuration. ChangeDetector detects production web application changes to help you identify when a change is the root cause of an application performance problem. After identifying change as the cause of a problem, you can use ChangeDetector to diagnose the problem. ChangeDetector gives you visibility into changes in code, application server configuration, and the configuration of connected systems that might be responsible for performance issues.
Because change occurs in many different parts of an application, ChangeDetector is also supported on the Environment Performance Agent (EPAgent). EPAgent Plug-ins enable you to gather application performance information from almost any source and monitor change data specific to your environment.
 
 
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About ChangeDetector
ChangeDetector is a set of Introscope extensions that allows you to monitor change in your application environment. ChangeDetector is directly integrated with Introscope to provide real-time change detection with low overhead. When a production problem occurs, ChangeDetector can help Introscope users correlate application changes with changes in application performance. This correlation allows you to isolate change as the cause of the problem.
ChangeDetector reports differences in application code, configuration, and environment in an agent, over multiple time periods. This reporting allows you to view how an application instance differs between time periods -- for example, between today and yesterday, or today and last week.
With ChangeDetector, you can view this information:
  • Graphical views of change events
    The events include text and binary files, archives, system properties, application code, database tables, and specific database query result sets.
  • Change-event details including the time that a change was detected, nature of the change, and difference between versions for text files.
  • The ChangeDetector dashboard, to see a high-level view of change data.
  • Hierarchical and historical views of changes today, yesterday, and last week
  • Change reports to summarize changes in an application.
ChangeDetector and Your Introscope Environment
This illustration shows the interactions between ChangeDetector components and Introscope:
APM Change Detector Overview
APM Change Detector Overview
Usage Scenarios
These scenarios illustrate using ChangeDetector to detect changes, correlate them to a problem, determine what changed, and decide how to correct the problem.
Triaging change as the cause of problems: Monday morning blues
Monday morning at 9:00, a banking online banking application starts experiencing performance problems. Introscope alerts the IT team that login and other critical transaction response times are degrading and breaching SLA levels. Irate users begin calling the customer service desk complaining that they can’t access their bank accounts. The call-center manager escalates the issue to the application support group, which immediately initiates an investigation.
The application support team reviews their Introscope dashboards to analyze the decline in performance. They look at the performance graphs, with ChangeDetector installed, they see the change data that is integrated directly into the ChangeDetector chart. The team reviews the change annotations and detailed information that is provided on the chart. They notice that a cluster of changes over the previous weekend preceded the current performance problems. Zooming in, they realize that the changes occurred over Saturday night during the application maintenance window. The team clicks through the Introscope Investigator tree view and inspects performance graphs of the various application instances. The similar graphs clearly show that each instance experienced a similar set of changes around the same time.
With change as a suspected cause of the problem, the application support team looks deeper. They click on each component of their application within the Introscope Investigator. The ChangeDetector view shows the changes that occurred for each component. Locking in on the application files, they notice that 37 files have changed, including 3 configuration files. ChangeDetector helps the team verify that each of the changes is a modification that was detected during the maintenance window. Selecting one of the application server configuration files, they compare the current version and the earlier pre-change version.
The cause is now clear. A database connection pool parameter that was set to 100 appears to have been changed to 10. With this information, a call by the application support manager to the development manager confirms a typing error. The slowdown was due to an unexpected change in the database connections.
Detecting a change before it becomes a problem: caught in the act
An Introscope alert displays. The application support team is informed that an unexpected change has occurred in their Java application. This change is not within the scheduled maintenance window. The application support manager starts reviewing their performance graphs. The application is behaving typically for now, but the graph shows that a few changes had occurred a couple of minutes ago. Placing the cursor on the changes, displays the change details. They appear to be modifications to system variables.
The application support manager begins by browsing the Introscope Investigator, looking for changes to the various application components. ChangeDetector provides a tree view of the changes in the application. The application support manager inspects the changes and notices that no changes occurred in the application and configuration files, or the APM database configuration. However, confirming the earlier Introscope alert, the support manager notices that four JVM and application server system properties have changed.
The application support manager clicks each of the detected variable changes to view the specific variable name, time that ChangeDetector reported the change, and the changed value. Apparently the Java heap size variables were lowered. If the application experienced an increased load, the change could cause problems. A check with the UNIX system administrator confirms that housekeeping was done and the potential effect of the changes was not realized. With the changes that are returned to their original values, a potential performance problem is averted.