  As data volumes continue to rise, manual inspection is becoming increasingly
untenable. In response, we present MacroBase, a data analytics engine that
prioritizes end-user attention in high-volume fast data streams. MacroBase
enables efficient, accurate, and modular analyses that highlight and aggregate
important and unusual behavior, acting as a search engine for fast data.
MacroBase is able to deliver order-of-magnitude speedups over alternatives by
optimizing the combination of explanation and classification tasks and by
leveraging a new reservoir sampler and heavy-hitters sketch specialized for
fast data streams. As a result, MacroBase delivers accurate results at speeds
of up to 2M events per second per query on a single core. The system has
delivered meaningful results in production, including at a telematics company
monitoring hundreds of thousands of vehicles.
