Analyzing Parallel Real-Time Tasks Implemented with Thread Pools

Despite several works in the literature targeted predictable execution models for parallel tasks, limited attention has been devoted to study how specific implementation techniques may affect their execution. This paper highlights some issues that can arise when executing parallel tasks with thread pools, which may lead to deadlocks and performance degradation when adopting blocking synchronization mechanisms. A new parallel task model, inspired to a realistic design found in popular software systems, is first presented to study this problem. Then, formal conditions to ensure the absence of deadlocks and schedulability analysis techniques are proposed under both global and partitioned scheduling.