I’m always surprised to see that the Citroen 2CV (CV: Cheval Vapeur, hence the name Deux Chevaux) has such a strong following, even in the United States. Granted, this car was the epitome of efficiency: It used minimum gas (60 miles to the gallon), was eminently practical, and its interior could be cleaned with a garden hose. Because the car was minimalist to the extreme, the gas gauge on the early models was a dipstick of some material, with marks to show how many liters of gas were left in the tank. For someone like me, who constantly forgot to consult the dipstick before leaving home, it meant that I would be out of gas somewhere far from a station almost every month. A great means of transportation failed regularly for lack of instrumentation. (Later models had a gas gauge.)
This shows how failure to monitor one element leads to the failure of the complete system — and that if you don’t manage everything you don’t manage anything, since the next important issue can develop in blissful ignorance.
The point is that we often approach application performance management from the same angle that Citroen used to create the 2CV: provide only the most critical element monitoring in the name of cost-cutting. This has proved time and again to be fraught with risk and danger. Complex, multitier applications are composed of a myriad of components, hardware and software, that can fail.
In application performance management, I see a number of IT operations focus their tools on some critical elements and ignore others. But even though many of the critical hardware and software components have become extremely reliable, it doesn’t mean that they are impervious to failure: There is simply no way to guarantee the life of a specific electronic component.
The Forrester APM reference model was designed to show what must be monitored to manage a business service performance. It specifically includes the monitoring of all components, hardware and software, virtual or physical. It puts the accent on the normalization and aggregation of all monitoring data into a single analytical reporting system so that: 1) different teams can cooperate using a unique source of information, and 2) critical issues can be extracted from the clutter of events coming from the monitors.
When planning an end-to-end application performance management solution, remember that end-to-end means that all components have to be included, which, by the way, implies that you must know all infrastructure elements that participate in the service. Like the latest 2CV models, the price may be a little bit higher, but you won’t end up stranded by the roadside.