About Overview Download Releases Download Nightly Tarball Changes Known Bugs License TODO Contributors Documentation User Manual Developer Manual JMeter Wiki Community Get Involved Mailing Lists CVS Repositories |
Visualizers
Visualizers process sample data during a test run - usually for the purpose of displaying the data visually. Adding a visualizer to your threadgroup is as simple as right-clicking on the threadgroup, and choosing the visualizer you want to add. Here is a rundown of some of the more popular visualizers.
Graphing Visualizer
The simplest and most straightforward, the graphing visualizer simply plots the data points on a graph. Each black dot represents a sample, its vertical height represents time in milliseconds that it took that sample to return. Average (blue) and standard deviation (red) are also plotted on the same graph, also in milliseconds.
View Results Visualizer
This visualizer allows the user to view the text returned from the sample. The usefulness of this visualizer depends on what you are testing. If you are testing web pages, you will be able to examine the HTML from each sample. You can hit the "Next" button repeatedly to view each subsequent sample. Please note that while you examine the samples, sampling continues, and all results are stored in memory, so you may want to stop the test after a few cycles and then examine the results. I typically use this visualizer initially to verify everything is going smoothly, and then I remove it and up the thread count for the real test.
File Reporter
Sometimes also called the File Visualizer, this visualizer returns no visual data, but rather stores the data to file. This file can later be viewed by choosing from the menu (Report->Analyze Data File), and browsing to the generated file. The data stored is very simple - URL and time in milliseconds. To use the File reporter effectively, be sure to Open the file before starting the test, and Close the file after you stop the test.
Spline Visualizer
The spline visualizer presents a smooth curve that represents the data from the entire test run. There are 10 points on the curve, each point represents an average of some subset of the sample run. For instance, if your test run has been running for some time, and you have 1000 samples, the first "point" on the curve will represent an average of the first 100 samples, the next will be for the second 100 samples, etc. These points are connected using spline curves, and allow users to see the entire history of the test and how the responsiveness of their application has changed over time.
Copyright © 1999-2001, Apache Software Foundation