h1. Instrumentation Recipe h2. Summary To be portable, Terracotta requires that classes are instrumented. This example builds on the Hello World example, by refactoring the {{int counter}} field of the Hello World example into its own class. In this example, because {{Counter.java}} is a custom class that will be shared in Terracotta, we must indicate to Terracotta that it must be instrumented. Notice in the tc-config.xml file we have added an {{instrumented-classes}} section, with a reference to the {{Counter}} class, which tells Terracotta to instrument the {{Counter}} class. h2. How to run (Note: A Terracotta Server instance is always required to run Terracotta. dso-java(.sh|.bat) is a wrapper script that adds Terracotta to standard java) *Node 1:* {code} $ javac *.java $ start-tc-server & $ dso-java Main count is 1 {code} *Node 2:* {code} $ dso-java Main count is 2 {code}