A system, method, and computer-readable medium for updating request routing information associated with client location information are provided. A content delivery network service provider receives a DNS query from a client computing device. The DNS query corresponds to a resource identifier for requested content from the client computing device. The content delivery network service provider obtains a query IP address corresponding to the client computing device. Based on routing information associated with the query IP address, the content delivery network service provider routes the DNS query. The process further includes monitoring performance data associated with the transmission of the requested resource and updating routing information associated with the query IP address based on the performance data for use in processing subsequent requests from the client computing device.