A system, method and computer program product configured to control a plurality of parallel programs operating in an n-dimensional hierarchical iteration space over an n-dimensional data space, comprising: a processor and a memory configured to accommodate the plurality of parallel programs and the data space; a memory access control decoder configured to decode memory location references to regions of the n-dimensional data space from indices in the plurality of parallel programs; and an execution orchestrator responsive to the memory access control decoder and configured to sequence regions of the n-dimensional hierarchical iteration space of the plurality of parallel programs to honour a data requirement of at least a first of the plurality of parallel programs having a data dependency on at least a second of the plurality of parallel programs.