The invention is directed to techniques for selecting a resource from several resources to process a request from a client. A client sends the request to a data communications device (e.g., network device or switch), which measures usage information from usage meters associated with each resource (e.g., server). The data communications device then makes a usage estimate for each server of the increase in usage required for that server to process the request from the client. Then the data communications device selects one of the servers depending on the usage estimates required to respond to the client's request. The data communications device can consider other factors such as the current level of usage, past usage, and the increased cost of responding to the request. In addition, the data communications device can consider the peak usage level of each resource already established in a current billing period.