When Should I Start Performance Testing?

The answer is simple: You cannot start performance testing early enough when building web applications!

For instance, it’s  even a good idea to start performance testing before a single line of code is written. By testing the base technology (network, load balancer, application, database and web servers) early on for the load levels you plan to support, you can better optimize your webserver and potentially avert business costs (i.e., lost sales) later on. Discovering that your hardware configuration is inadequate when the application is deployed can be very expensive to correct. Testing the server for its maximum stress level before development begins is  an excellent idea.

The costs for correcting a performance problem escalate as the development process moves forward. For instance, discovering a performance problem after an application or website is already deployed means countless man hours to correct the server issue—man hours that were already spent configuring the webserver (or application) the first time. 

During software development, all software engineers (and the quality assurance team) should have access to performance test tools to test their own code for performance and for parallel execution problems (e.g., problems caused by database locks or other mutexes). Software engineering managers for web projects are realizing that each developer must be responsible for both the functionality and performance of code.

As soon as several web pages are working, the first load tests should be conducted by the quality assurance team. From that point forward, performance testing should be part of the regular testing routine each day for each build of the software.