Right Java tools for J2EE, Web Service, Grid and more

Table of Contents

• Overview
• Prerequisite
• Testing procedure
• Rehearsal and Real Test
• Stress test case
• Stress configuration
• The way to stress: doze versus number of VM
• Reports
• The format of the raw report file

Overview

SuperStress is a J2EE stress tool to test EJB server's performance and robustness. It simulates heavy usage load and reports how your EJB applications and the server behave when hundreds, even thousands of users concurrently call.  A minimal number of client computers can generate the same effect as a large number of real users manually do. It is a visual tool. It is very simple and powerful tool.

SuperStress is very user friendly. You do stress test visually:

• SuperStress uses EasyEJB as underlying facility for visually setting test cases. No programming is needed.
• Test cases are configurable visually. No programming is needed.

All the settings are done at the time a stress test session is launched. No programming is required. Test cases can be saved, restored and edited at any time.

SuperStress provides flexible data input facilities. Data is editable when a test case is launched.

Many other Web testing tools test web applications as a whole, while SuperStress tests the EJB server itself, and helps finding the bottleneck.

SuperStress is helpful in the following scenarios:

• You want the test to focus on the EJB server and EJB applications, not the web server, nor Servlet, nor JSP.
• Your server provides services for direct clients. There is no Servlet nor JSP on your server side in between.

SuperStress is based on EasyEJB technology. This document assumes that you are familiar with EasyEJB.

Each stress item is either a peek or poke item. Stress items can be mixed in any order. SuperStress repeatedly calls each item, dozing a short period between two calls.

Simplicity without compromising the power is a high priority of the design of the system. With simplicity, you have less chance to introduce bugs in your test cases. When you have to program in the case of using Dynamic Argument for your methods, SuperStress does not ask you to learn any new things (except for a small class to inherit from: only a few lines).

Prerequisite 

See Prerequisite in Installation for general prerequisite.

Testing procedure

1. Create a stress test case by selecting EJB's methods visually, which are shown by SuperStress.
2. Use SuperStress to call the test case repeatedly as a rehearsal.
3. Launch a real test by generating one or more Java Virtual Machines. Each Stresser is an independent stress tester.
4. Analyze graphical reports which are generated by SuperStress.
 

Data input

SuperStress provides two ways for input data:

• Keyboard: Use your keyboard to key in data. This option is for simple data types.
• DynamicArgument: SuperStree calls a DynamicArgument to get input data.  

Data is editable at the time a stress test is launched.

Rehearsal and real Test

SuperStress provides a comprehensive way to visually construct stress test cases based on EasyEJB. When you prepare your test case, you can use the Stress Panel as a rehearsal. It is just like EasyEJB. When you are ready, you can launch Stressers, which are real testers. Stressers are more configurable than rehearsals.

There are algorithm differences between Rehearsal and Stresser:

• Rehearsal: like PeekPoke, the interval (Pace) is performed at the end of each PeekPoke cycle.
• Stresser: the interval (Doze time) is performed after each remote method invocation.
   
   

Stress test case

Stress test cases consist of the EJB method calls in a defined order.  They are the sources of stress testing.
 
 

Stress configuration

SuperStress is highly configurable. Configuration is done visually using GUI when a stress test session is launched. No programming is required.

Testing configuration parameters are:

• Number of Java Virtual Machines.
• Virtual Machine delay time (the period before starting the next VM).
• Doze time (the period between two EJB calls).
• Doze decrease.
• Doze minimum.
• Doze decrease delay time (the period before decrease doze time).

The way to stress: doze versus number of VM

Both decreasing doze time and increasing number of VMs (Virtual Machines) can intensify the stress. But they simulate different scenarios.

If a Web Server (Servlet and JSP) is the main client of the EJB server, the most of usage load comes from one VM (or limited number of MVs). Use of the single VM mode with a small doze time would be appropriate.

If many independent clients call the EJB server simultaneously, the usage load comes from different VMs. Use the multiple-VM mode would be appropriate.
 

Reports

Reports are the results of stress testing. Each Stresser generates one raw report file, which is named by the report name with an extension. The extension is a number indicating which VM it is for. All report files are under the directory below:

   <installed directory>/stress/report (Unix)
   <installed directory>\stress\report (Windows)

The default <installed directory> is AceletSuper.

SuperStress reads all raw report files and generates graphical reports for the test case.
 
 

The format of the raw report file

The format of the raw report file is:
  The first line is description.
  The second line is the starting time.
  Many report lines follow.

Each report line is in the format of:

<item name>`<call time>`<return time>`<doze time>`<return value>`<method arguments>`<home method arguments>

Back quotes are delimiters which are the pattern for further parsing.