A computer-implemented method operable in a content delivery service (CDN), includes, by a collector system: (A) receiving at least one event stream of event data, said event data relating to operation of at least one type of CDN service, each event of said at least one event stream comprising: (i) a timestamp for said event, (ii) information relating to said event; and producing state data relating to information represented in said event data while being able to asynchronously respond to queries relating to said state data.