TIGER: topology-aware task assignment approach using ising machines

Optimal mapping of a parallel code's communication graph is increasingly important as both system size and heterogeneity increase. However, the topology-aware task assignment problem is an NP-complete graph isomorphism problem. Existing task scheduling approaches are either heuristic or based on physical optimization algorithms, providing different speed and solution quality tradeoffs. Ising machines such as quantum and digital annealers have recently become available offering an alternative hardware solution to solve certain types of optimization problems. We propose an algorithm that allows expressing the problem for such machines and a domain specific partition strategy that enables to solve larger scale problems. TIGER - topology-aware task assignment mapper tool - implements the proposed algorithm and automatically integrates task - communication graph and an architecture graph into the quantum software environment. We use D-Wave's quantum annealer to demonstrate the solving algorithm and evaluate the proposed tool flow in terms of performance, partition efficiency and solution quality. Results show significant speed-up of the tool flow and reliable solution quality while using TIGER together with the proposed partition.