The DashBoard of Google App Engine presents interesting results, but what is the truth behind this data? I started by deploying a simple Java EE (JSP / Struts / Strus menu) and deploying it in the Google App Engine cloud at http://kbdsoft.appspot.com/

To check the validity of  the values presented by the DashBoard of Google App Engine, we use a simulation tool in the classical world of performance studies: the famous Jmeter

• Install a simulation tool load (Download Jmeter from http://jakarta.apache.org/jmeter/ )
  
  
  
  
• Launch Jmeter Script and create a simulation application execution

Run a simulation of 20 concurrent virtual users (20 Threads).

The scenario is executed 100 times.

http://kbdsoft.appspot.com/

http://kbdsoft.appspot.com/pagesManagement.do

http://kbdsoft.appspot.com/menuManagement.do

http://kbdsoft.appspot.com/user.do

http://kbdsoft.appspot.com/audit.do

http://kbdsoft.appspot.com/rolesManagement.do

http://kbdsoft.appspot.com/index.do

We note that at the beginning of the simulation

At the end of simulation the graph Request / Second becomes

The Google App Engine’s Dashboard allows you to track the behavior of the application.

Thus, after the full execution of the script, the results presented by the GAE's Dashbord are summarized as follows:

On the other hand, after the end of the execution of the script, the results presented by Jmeter are summarized as follows :

The results of Jmeter Vs results GoogleApp Engine

There is a good concordance of results (although it sure is a short simulation . For more detailed results, it must be remembered that performance measures should follow a statistical study and use the laws of large numbers)

The results shown by Google are validated by the results of Jmeter

We can rely on the DashBord.

Conclusion:

For this first test : it took me half an hour to deploy a simple old Struts based application on the Google cloud

No changes were necessary!  Note, there was no transaction, database, Spring, Hibernate..

The Google App Engine Dashboard allows monitor the activity of the application and see the logs and the response time.

Working with GoogleApp Engine is :

• Easy
• Allows recycling of "old" Java
• The Dashboard provides information close to the reality and verifiable