We engineers love measuring stuff. Whether it helps us solve an immediate problem, gets us ready for a bad day or just because most of us are information junkies, we love keeping track of metrics. The spectrum of what can be measured is very wide. It can include data from every part of our system: from technical metrics such as disk space or RPM, through UI metrics like page load times, to business KPIs such as revenue, conversion rates and so on. When choosing which metrics to collect, we usually start with the obvious ones: those that reflect the current state of the system (e.g., CPU, memory and load). There are quite a few articles and blog posts about these metrics, so I’m not going to discuss that here. Rather, I would like to focus on metrics that reflect the user experience.
Here are the four metrics that we at BigPanda see as the most important in this category: