Practical Example of Optimal Scheduling of Hybrid Quantum-Classical Workflows

Quantum computers (QCs) and high-performance computing (HPC) systems are increasingly being integrated to support hybrid quantum-classical workflows, in which quantum and classical tasks must be coordinated across heterogeneous resources. This integration creates new scheduling challenges arising from resource contention, task dependencies, data movement, queueing delays, and the limited availability of quantum devices. In this paper, we study the problem of optimally scheduling hybrid quantum-classical workflows on HPC-QC systems. We formulate scheduling strategies that account for both the structure of the workflow and the topology of the underlying computing resources, with the goal of improving end-to-end execution efficiency. By exploiting dependencies between quantum and classical tasks, as well as locality and connectivity properties of the available resources, our approach seeks to minimize workflow completion time while improving coordination between HPC and QC components. We demonstrate these ideas through a proof-of-concept implementation integrated with an HPC workload manager and evaluate it using a sample-based quantum diagonalization (SQD) workflow.