Multi-criteria scheduling of pipeline workflows (and application to the JPEG encoder)

International audienceMapping workflow applications onto parallel platforms is a challenging problem, even for simple application patterns such as pipeline graphs. Several antagonist criteria should be optimized, such as throughput and latency (or a combination). A typical application class is digital image coding, where images are processed in steady-state mode. In this paper, we study the general bi-criteria mapping problem (minimizing period and latency) for pipeline graphs on communication homogeneous platforms. We present an integer linear programming formulation for this NP-hard problem. Furthermore, we provide several efficient polynomial bi-criteria heuristics, whose relative performance is evaluated through extensive simulations. As a case study, we provide simulations and MPI experimental results for the JPEG encoder application pipeline on a cluster of workstations