1. A system comprising: at least one processor: a memory connected to the at least one processor; and a cloud-scale query execution platform that supports distributed stream processing comprising a streaming job manager that monitors execution information about streaming jobs executed by a plurality of vertices executing on a plurality of computing devices, the streaming job manager receiving execution progress information and data dependencies for the plurality of vertices, each vertex of the plurality of vertices configured to process events associated with one or more streaming jobs, and each event being labeled with a sequence number used by at least the streaming job manager to describe and track dependencies between input, output and state of a vertex.