Real User Measurements

Chapter 2. RUM: Making the Case for Implementing a RUM Methodology

It turns out umpires and judges are not robots or traffic cameras, inertly monitoring deviations from a fixed zone of the permissible. They are humans.

Eric Liu

As mentioned in the Chapter 1, Real User Measurements (RUM) are most reasonably and often contrasted with Synthetic Monitoring. Although my subtitle to this chapter is in jest, it is not a bad way to understand the differences between the measurement types. To understand the pros and cons of RUM, you must understand broadly how it works.

RUM versus Synthetic—A Shootout

So, where does RUM win? Where do synthetic measurements win? Let’s take a look.

What is good about RUM?

• Measurements are taken from point of consumption and are inclusive of the last mile.

• Measurements are typically taken from a very large set of points around the globe.

• Measurements are transparent and unobtrusive

• Can provide real-time alerts of actual errors that users are experiencing.

What is bad about RUM?

• Does not help when testing new features prior to deployment (because the users cannot actually see the new feature yet).

• Large volume of data can become a serious impediment.

• Lack of volume of data during nonpeak hours.

What is good about Synthetic Monitoring?

• Synthetic Monitoring agents can be scaled to many locations.

• Synthetic Monitoring agents can be located in major Internet junction points.

• Synthetic Monitoring agents can provide regular monitoring ...