In some embodiments, a method receives a request for an instance of media content in a current session. A state is retrieved for content delivery networks that is determined for a session in a set of sessions. The state includes a first set of values for a performance metric, and the first set of values is associated with the content delivery networks. The method determines a second set of values for the performance metric for the current session. The second set of values is associated with the content delivery networks. A content delivery network is selected for the request in the current session based on treating the current session as a session in the set of sessions. The session for the current session is after the session for the state in the set of sessions.