1. A method for monitoring a business transaction, comprising: recording performance data for each of a plurality of methods of a network application, the performance data stored by an agent in a header of an execution thread that executes the method, the agent stored on a machine that executes the plurality of methods; ignoring the performance data for one or more of the plurality of methods that satisfy a threshold; generating a call graph from the performance data, the call graph indicating the root method of the business transaction and each method called as part of completion of the business transaction; and storing the performance data for one or more of the plurality of methods having a root node that does not satisfy a condition.