1. A computer-implemented method for processing a continuous data stream, the method comprising: receiving a record of the continuous data stream; generating, by an ingest node, one or more graph-update operations based on the record; assigning a sequence number to the one or more graph-update operations; distributing the one or more graph-update operations with the sequence number to a plurality of graph nodes; recording the sequence number in a global progress table after the one or more graph-update operations are stored by the plurality of graph nodes, the global progress table comprising a vector including the sequence number and another sequence number assigned by another ingest node that generates and distributes one or more other graph-update operations to the plurality of graph nodes; defining an end of an epoch based on the global progress table based on the vector; and producing a graph structure snapshot by executing the one or more graph-update operations that are stored in the plurality of graph nodes and are within the epoch and by executing the one or more other graph-update operations.