Sunday, October 19, 2014

Client-Side metrics versus Performance KPIs

Am happy to be back again blogging some useful stuff after a long time !!

Recently when i happened to have a discussion with one of the performance test engineer, I realized to bring this point elaborately looking at his misunderstanding.

The Client-Side performance is of great importance as it assesses end-user experience. It is vital to understand what is happening in the browser & its runtime (JavaScript , DOM). Optimizing the front-end performance from a single user point of view is very vital before testing an application with high user loads. The front-end, client-side performance optimization is quite simple compared to back-end performance optimization where lot of detailed analysis such as code profiling, hardware upgrade, etc. is required.

I experienced it several times & learnt in a hard way that client-side performance is always considered trivial as it is simple and can be quickly performed with right set of tools.

There are quite a good number of tools to do this analysis. To mention a few, Google's WebPageTest tool, Yahoo's YSlow extension, FireFox's FireBug extension, Google's pageSpeed, Ajax Dynatrace for IE, Speed Tracer extension for Google Chrome, etc.


The Key Performance Indicators (KPIs) like Response Time, Throughput, etc cannot be called as client-side metrics. May be you get to see these metrics through the performance test tool, but it is nothing to do with client-side metrics. The KPIs usually represent the system performance after the end of a performance test. These should be called as System Performance metrics or Performance KPIs.