DREAM: A Dynamic Ripple-Effect-Aware Meta-Scheduling Scheme for Cloud-Edge-End Collaborative AI Computing
Cloud-edge-end collaborative Artificial Intelligence (AI) computing requires schedulers that allocate heterogeneous resources for Directed Acyclic Graph (DAG)-structured workflows across network tiers. Cross-tier data transfers create ripple effects where a single placement decision propagates delays to downstream tasks, degrading end-to-end completion rates. This paper presents DREAM, a Dynamic Ripple-Effect-Aware Meta-scheduling scheme in which Critical Path Lookahead Scheduling (CPLS) performs bounded-depth trajectory planning with soft reservations for critical tasks, while Opportunity-Cost-Aware Placement (OCAP) evaluates non-critical tasks through a four-component cost covering immediate efficiency, ripple effect, load stability, and opportunity cost. Extensive simulations demonstrate that under the heavy load of 600 tasks, DREAM sustains a task completion rate of ~66%, exceeding classical heuristics by over 10 percentage points. At the extreme load of 1000 tasks, the system utility score improves by 47% over HEFT. Robustness experiments verify competitive performance across multiple DAG topologies and estimation-noise levels.