Chapter 5. Using the main graphical introspection tools
This chapter covers
- Monitoring applications with Appmon and WebAppmon
- Managing processes with Pman
- Using the source-level debugger
- Inspecting tables with the Table Viewer
- Using the Erlang Toolbar
You’ve learned a lot about Erlang and OTP at this point. In the last chapter, we introduced OTP applications and supervisors. We’ve talked about how these are living things in an Erlang system. In this chapter, we show you. Erlang provides a number of graphical tools for inspecting a running system that are a great help for understanding what’s going on. They’re really good at helping you visualize things like processes, applications, and supervisor hierarchies. The first tool we introduce is called Appmon; it’s specifically made for looking at things from an application and supervision perspective.
As the name indicates, Appmon is a tool for monitoring OTP applications. It lets you visualize the applications that are running in the system, as well as their supervisor hierarchies; see the current status of the processes; and perform some basic operations on them.
Before we do too much explaining, let’s get Appmon running. Start an Erlang shell, and enter appmon:start():