Abstract: A method and apparatus for identifying a minimum call tree data structure from a plurality of call tree data structures are provided. With the apparatus and method, call tree data structures are generated for two or more executions of a build of a computer program. The apparatus and method perform a “tree-minimization” operation in which the two or more call trees generated during runs of the computer program are walked and only those nodes that are present in each of the tree data structures are maintained in a minimized tree data structure. In addition, the minimum values for these common nodes are maintained in the minimized tree data structure. In this way, asynchronous events are removed from the minimum tree data structure and analysis may focus on those areas of the computer program that are consistent between runs of the computer program.