Skills of a Performance Test Engineer – A Software Testing Company’s perspective

Overview

The pertinent question in the minds of every Software Testing Companies is about the desired skill sets of a Performance Test Engineer they intend to hire. Should they look out for a Performance Test Engineer with sound knowledge of functional testing or a fresher with good coding skills be hired as a Performance engineer. In order to select the most appropriate candidate the Software testing companies should first evaluate their own requirements and understand the extent to which Functional testing knowledge is desired for the profile of Performance Test engineer. The article touches on important aspects to be considered while selecting the most appropriate resource for Performance Testing.

Performance vs Functional Testing

Performance testing is the process of determining the effectiveness of a computer, network, software program or device and help measure server side, the client side and the network statistics to verify that a system meets the specifications claimed by its manufacturer or vendor. Functional testing ensures that the program physically works the way it is intended. It also ensures that the program conforms to the industry standards relevant to that environment.

Functional testing typically involves:

I. The identification of functions that the software is expected to perform

II. Creation of input data based on the function's specifications

III. Determination of output based on the function's specifications

IV. Execution of the test case

V. Measurement of actual and expected outputs

Need of Functional Testing knowledge for a Performance Tester

Functional testers can always raise alarm early as they are the one who can check the degradation of performance.

1)A functional tester has a better idea of response times of different applications whereas a performance tester has to rely on the metrics generated by the load test tool until benchmark is determined.

2)Adding functional/GUI/end-user scripts to load testing can be useful in many ways- it helps in validation of protocol-based scripts, one can see end-user performance, it covers more functionality, on can also catch more subtle issues related to timing/order of downloading etc.

3)When we get to the point wherein we start testing familiar systems again and again, a kind of routine performance regression testing, the process becomes somewhat more similar to functional testing. And functional testing has developed some interesting methods of choosing what all tests to run in such scenarios.
A Software testing company will prefer hiring a Test engineer who has a good understanding of the Software application, including the hardware/software resources, the environment and network bandwidth. This will ensure that the Application can be tested effectively for Performance in real world scenario with a faster turnaround time. The performance tester does not have luxury of extra time and has to work under strict time-limits. They get hands on only at the final stage before the release of the application. But IDE and rick framework provided by the tools give a jump start to above challenges. Performance tester’s most important trait is analyzing skills – with good understanding of the application workflow, transactions so that coding skills can be used to script the workflows.
Functional testers have better knowledge about scenarios and work-flows for different type of applications. With their experience they get to know whether a particular behavior in the application is actually an error or just an uncommon application behavior.

With growing need Software testing companies tend to look for expert performance testers having prior functional testing knowledge. This can save considerable time and cost of testing process as during performance testing they might get stuck in a situation where it is hard to infer the response of the application. They can even implement some practices used in functional testing e.g. use of module based scenario selection instead of system based scenarios, in case of high depth modules that give higher response times during load testing an application. Such testers can also refer to specification docs to check for any change in the application and update their scripts accordingly.

In a nutshell a successful Software testing company should be able to strike a perfect balance between the teams of Functional test Engineer and a Performance Test Engineers for effectively testing an Application in fastest turnaround time. Alternatively the company should ensure that a performance tester has knowledge of functional testing in addition to scripting and protocol’s knowledge. This will remove all the bottlenecks faced by testers during performance testing.