Techniques described herein provide for real-time observation of utilization of one or more resources by a system in response to an input. The real-time observation by a system may occur in an environment in which end users supply inputs to the system (e.g., a production environment). In various embodiments, a server system may provide a service to a client system. A client system may take advantage of this service by sending an input to the server system. In response, the server system may perform the provisioned service using the input from the client system. In connection with the service, the utilization of resources (e.g., by a process) and/or the client system-supplied input may be recorded, such as when resources are utilized in an unexpected or interesting manner. These records may be used at a later time for testing and analysis.