private void doCompareResults(
      PerformanceSuiteResult oldResult, PerformanceSuiteResult newResult, String testMethod)
      throws PerformanceException {
    for (String className : oldResult.getResults().keySet()) {

      PerformanceClassResult oldClassResult = oldResult.getResult(className);
      if (oldClassResult.getMethodResult(testMethod) != null) {
        oldClassResult
            .getMethodResult(testMethod)
            .compareResults(
                newResult.getResult(className).getMethodResult(testMethod),
                oldClassResult.getPerformanceSpecs().resultsThreshold());
      }
    }
  }