A graph-based computation has a plurality of nodes representing graph components connected by one or more links representing data flows between the components. Preparing the computation includes: identifying at least a first set of components to process a plurality of transactions in the computation; and associating with a first transaction a first group of one or more data records and data operations corresponding to the data records, and associating with a second transaction a second group of one or more data records and data operations corresponding to the data records. Executing the computation to process at least the first and second transactions includes delaying execution by the first set of components of a data operation corresponding to an initial data record of the second group until after execution by the first set of components of a data operation corresponding to a final data record of the first group.