Warehouse reshuffling: Insights and optimization

•Quantifies and compares the impact of different operational assumptions.•Develops the first mathematical model formulation of the general warehouse reshuffling problem.•Develops heuristic solutions that work well for large practical problem instances.•Proves when minimizing reshuffling moves does not necessarily minimize reshuffling distance.

Warehouse reshuffling is a reorganization strategy that consists of repositioning items by moving them sequentially. This study investigates how to optimize warehouse reshuffling and quantifies the effect of common assumptions. A mathematical programming formulation for the general warehouse reshuffling problem, the complexity of the problem, several heuristics based on the problem structure, a formal proof delimitating instances where double-handling can be a productive move, and managerial insights on the performance of reshuffling policies in various environments are presented. Experimental results suggest that the proposed heuristics improve upon a benchmark heuristic by relaxing how cycles are handled and incorporating double-handling.