Performance Testing


In the current era, when you hardly have any stand alone desktop application Performance, Load and stress Testing becomes key to the success of your application. Performance testing comes under non functional testing.

Performance testing is normally used with Load testing and stress testing. Some people even use these terms interchangeably, which is not correct. Common factor among these testing type is the simulated load, but there are subtle difference in performance, load and stress testing. We will explore these in some detail and try to make the difference between these testing clear.


Performance Testing

Performance testing is conducted after the completion of functional testing. Performance testing is normally conducted during the System Testing phase. Objective of performance testing is not to find functional defect in the system, it is assumed that functional defects have been identified and removed from the system.

Performance testing is usually conducted for web applications. Main objective of performance testing is to get information with respect to response time, throughput and utilization under a given load. In order to perform performance testing on the web application, you need to know at least these two things

Expected load it could be in terms of concurrent user or HTTP connections.

Acceptable response time

During performance testing whole system can be optimized at various levels. It can be optimized at 

  • Application Level
  • Database level
  • Operating system level
  • Network level

Performance testing can be performed as a white box or black box activity. In white box approach, system is inspected and performance tuning is performed where ever possible to improve performance of the system. In black box approach, test engineers can use tools that simulates the concurrent users/ HTTP connections and measure response time. 

When the result of the performance testing indicates that performance of the system is below the acceptable level, you start tuning application and databases. You need to make sure that system runs as efficiently as possible on the given hardware/OS combination. If even after tuning application, databases and other parameters performance of application is under acceptable level, probably it is time to scale your hardware, database and web servers.





Scalability Testing

Performance & Security Testing Checklist