Bridging the gap between systems-oriented research and queueing theoretic works on parallel systems

The goal of the VaMoS project is to bridge the gap between systems-oriented research and queueing theoretic works on parallel systems to create models which reflect the performance of real systems and their scaling behavior.

Project phase 2 focuses on parallel systems with barriers. Typically this means that jobs are divided into tasks which will be serviced in parallel by a cluster of workers, but that the tasks are constrained to start, and possibly complete, simultaneously. There may also be intermediate synchronization points. This type of constraint is common in machine learning workloads, and support for barrier execution mode has very recently been added to some map-reduce engines in order to support these types of workloads. These barrier constraints have major performance implications, because they can force workers to sit idle, waiting for a single long-running task to finish.