About company Our development services Portfolio. Case studies Support Testimonials Contacts Brutka Ltd: web site development and custom software development

Information technology news archive

How to Monitor and Analyze a Load Test Result

Monitoring a Running Test or Analyzing a Completed Test
A load test result contains performance counter samples and error information collected periodically from the computers-under-test. A large number of performance counter samples can be collected over the course of a load test run. The amount of performance data collected depends on the length of the run, the sampling interval, the number of computers under test, and the number of counters to collect. For a large load test, the amount of performance data collected can easily be several gigabytes.
By default, the test controller spools all collected load test sample data to a database while the test is running. Additional data, such as timing details and error details, is loaded into the database when the test completes. The performance data for a completed test can be loaded from the database and analyzed by the Load Test Analyzer. A completed test result loaded from a load test result database is called a post-run result.
While a test is in progress, a condensed version of the performance counter data is maintained in memory by the Load Test Monitor. To prevent the results memory requirements from growing unbounded, the load test monitor maintains up to 200 samples for each performance counter. This includes 100 evenly spaced samples that span the run's current elapsed time, and the most recent 100 samples. The result that is accumulated during a run is called an in-progress result.
Attaching Notes to a Load Test Result
A description and analysis notes can be attached to a load test result. The Analysis command on the context menu of either the Load Test Analyzer or Load Test Monitor starts the Analysis dialog box.
Viewing a Load Test Result
Both the Load Test Analyzer and the Load Test Monitor provide a graph and a table view of a load test result.
Differences Between Analyzer and Monitor
Although the user interfaces are similar, the Load Test Analyzer and Load Test Monitor differ in the following ways.

Unique to the Load Test Analyzer (viewing a post-run load test result):

Provides a single graph mode (zooming), which enables you to zoom in and out on data that is contained within any time range.
Provides the Show Min Max Lines graph option, which enables you to view high and low water marks on the graph for collapsed data.
Table views provide Percentile statistics.

Unique to the Load Test Monitor (viewing an in-progress load test result):

Provides two graphing modes: collapsing and scrolling.
Provides an option to toggle between collapsing and scrolling modes.
Provides a "sample plot" on the graph when the mouse hovers over a performance counter that has not been plotted.
Provides a progress indicator with time remaining in the test.
Provides a stop button on the main toolbar to stop the load test.
Provides a status bar link that appears when a test completes, to transition the result from an in-progress result to a post-run result, and thus switch the viewer from the monitor to the analyzer.



More IT news, prices and information