Techniques and systems for providing optimization of traffic routing for data centers are disclosed herein. In some embodiments, a method may include identifying a plurality of available source sites and paths or routes between an online service provider (OSP) and a destination prefix. A traffic manager may measure a cost for each of the plurality of available paths. In some instances, the traffic manager may also measure a performance value for each of the available paths. The traffic manager may then select one of the available source sites and paths as a preferred source site and path that has a minimized cost for an instance of the performance value when compared to other paths of the plurality of available source sites and paths. In further embodiments, the traffic manager may rewrite a routing table and DNS mapping to implement the preferred source site and path as the default source site and path between the OSP and the destination prefix.