Various examples are directed to systems and methods for network virtualization for web applications. For example, a WAN controller may receive from a backend query processor, a first tenant user query table that describes a first set of query types for a first user. The first set of query types may comprises a first query type having a first computational weight and a second query type having a second computational weight less than the first computational weight. The WAN controller may determine that a first network path to a web application data center is less congested that a second network path to the web application data center. The WAN controller may send a first flow entry to a first network appliance on the first network path instructing the first network appliance on the first network path to send packets associated with queries of the first set of query types to a second network appliance on the first network path.