1. A method to manage Quality of Service (QoS) aware captive aggregation with datacenter testing through middleware, the method comprising: receiving a job at a datacenter, wherein the received job exceeds a capacity of the datacenter; determining a suitable subcontract datacenter for at least one of a plurality of existing jobs at the datacenter by communicating with the middleware, the middleware configured to: deploy a reference task to a plurality of candidate datacenters to perform identical tasks on resources, wherein the reference task is a surrogate task with a plurality of calibration points, and the surrogate task is configured to deploy in a model of an actual task application with similar levels of communication between blocks and computation between actions; and receive data on an actual cost and resource consumption for performing the reference task; forwarding the at least one existing job to the suitable subcontract datacenter based on the received data; and upon receiving results of the forwarded job, providing the results to an originating client, wherein a QoS for the forwarded job is maintained at a substantially same level as if the job was performed at the datacenter.