Systems and methods for monitoring performance associated with fulfilling resource requests and determining optimizations for improving such performance are provided. A processing device obtains and processes performance metric information associated with processing a request corresponding to a set of resources. The processing device uses the performance metric information to identify a subset of the resources corresponding to a display location associated with a visible portion of a display and to assess performance related to processing of the identified subset of the resources. In some embodiments, the processed performance data may be used to identify timing information associated with the subset of the embedded resources. Aspects of systems and methods for identifying and testing alternative resource configurations corresponding to the content associated with the original set of resources and for determining whether to recommend a resource configuration for improving performance of subsequent client requests for the content are also provided.