There is a common issue I deal with when speaking to end users trying to monitor applications. This confusion is partially created by vendors who would like to position themselves in the hot APM market, yet they clearly don’t enable performance monitoring. These vendors are slowly starting to correct the messaging, but many have poor market understanding, and continue to confuse buyers.
There are two types of monitoring technologies, one is availability monitoring and the other performance monitoring. Before embarking on a performance monitoring journey (this applied to both application performance monitoring and network performance monitoring) there should be a good foundation of availability monitoring. Availability monitoring is the easier of the two, it’s inexpensive, effective in catching major issues, and should be the staple of any monitoring initiative. We recommend unified monitoring tools (See Post : http://blogs.gartner.com/jonah-kowall/2013/11/12/unified-monitoring-note-presentation-and-client-interest/) to handle availability monitoring across technologies with a single offering.
When looking at server monitoring tools, they do more than monitor the server and OS components, but also handle the collection of data from instances of applications on the OS instances. The data collected includes metrics and often times log data which shows major issues in application availability or health. This is often what people are looking for, and many vendors call these requirements “APM”, but that’s incorrect. We call this server monitoring and/or application instance monitoring. These are availability tools and not performance monitoring tools.
The area APM tools differ from server monitoring tools is in multiple ways. APM tools live within the application and provide end user experience data from the user through the distributed application components. They are able to monitor and trace transactions across tiers of the application. Similarly other tools which monitor application performance can reside on the network, while these don’t have the level of granularity when tracing transactions and getting internals of applications they certainly can detect performance deviations of application components and often times can handle other application technologies.
Hopefully this helps clear things up, and please reply here or contact me on Twitter @jkowall