LSTF: A new scheduling policy for complex real-time tasks in multiple processor systems. We propose a new algorithm, least space-time first (LSTF), for dealing with the general complex-task-multiple-processor model. The results of the proof and simulation shown that LSTF outperforms other established heuristic algorithms (such as earliest-deadline-first) in the sense that it minimizes the maximum tardiness of a set of tasks. LSTF can gracefully incorporate some realistic overhead assumptions, such as context switch.