基于NoC分布式多核系统中任务迁移的实现

摘要

In order to decrease task migration overhead in distributed multi-core system, a low-cost task migration scheme is implemented on the distributed multi-core system based on Network on Chip(NoC). The task migration scheme depends on the distributed multi-core system message passing interface, in which program is independent of task mapping. Task is remapped by updating task mapping table. The task state including task stack and task control block in μC/OS-II operating system is transferred to another node, on which the migrated task restores execution. The task migration scheme needs not transfer task code, and task state saving does not use checkpoints. Experimental results show that in this migration scheme, the task migration scheme has little influence on task execution and immediate response to migration request. Therefore, the task migration scheme is low cost and can meet real-time requirements in system.%为降低多核系统中任务迁移的开销，在片上网络分布式多核系统的基础上实现一种低开销的任务迁移方案。借助于多核消息传递接口模型中并行程序与任务映射无关的特点，采用更新任务映射表的方式完成任务的重新映射，通过在μC/OS-II 操作系统中传递任务的堆栈以及任务控制块实现任务状态在多核节点间的传递，任务迁移到另一节点后能够恢复原来的状态继续执行，不需要传递任务代码，并且任务状态的保存不需要迁移点。实验结果证明，该任务迁移方案能够及时响应任务迁移请求，具有低开销的特点，可较好地满足系统中任务的实时性要求。