1. A computer-implemented method operable in a content delivery service (CDN), said CDN comprising multiple CD services, said method operable on at least one device comprising hardware including memory and at least one processor, the method comprising: by a collector system: (A) receiving multiple event streams of event data, said multiple event streams comprising event data from a plurality of CD services in said CDN, each event of said event streams comprising: (i) a timestamp for said event, (ii) information relating to said event; and (B) producing state data relating to information represented in said event data of said multiple event streams while being able to asynchronously respond to queries relating to said state data.