1. One or more computer-readable storage media storing computer-executable instructions that, when executed, configure one or more processors to perform actions comprising: determining host status information for a plurality of hosts, each host comprising a plurality of applications, wherein the host status information comprises a health and load table including a plurality of entries, each entry of the plurality of entries associated with an application of the plurality of applications, each entry of the plurality of entries comprising: an application identifier for a particular application of the plurality of applications; information characterizing at least one status of the particular application; and at least one load balancing directive regarding the particular application; implementing a message protocol between at least one host and one or more load balancing units, the message protocol usable for communicating host status information between the at least one host and the one or more load balancing units when the host status information is updated; communicating the host status information from the at least one host to the one or more load balancing units, wherein the one or more load balancing units each comprise a consolidated health and load cache that stores application— specific health and load information for the plurality of applications that are executing on the plurality of hosts; receiving the host status information from the at least one host; and making load balancing decisions responsive to the received host status information.