Memory-processor co-scheduling in fixed priority systems
Memory-processor co-scheduling in fixed priority systems
复制标题
固定优先级系统中的内存-处理器协同调度
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
G. Buttazzo
中科院分区：
文献类型：
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作者：
Alessandra Melani;M. Bertogna;V. Bonifaci;A. Marchetti;G. Buttazzo
采用多核平台的实时系统的一个主要障碍是由于内存争用的干扰特性的困难。多个核心可以同时访问共享内存和通信资源的简单事实在时序和可扩展性分析中引入了显着的悲观主义。为了解决这个问题，已经提出了可预测的执行模型，将任务执行分为两个连续的阶段：存储器阶段，其中所需的指令和数据被预取到本地存储器（M阶段），以及执行阶段，其中任务在没有存储器争用的情况下执行（C阶段）。解耦存储器和执行阶段不仅简化了时序分析，而且还允许通过适当的协同调度算法对存储器和执行阶段进行更有效（和可预测）的流水线操作。在本文中，我们采取了进一步的智能协同调度算法的设计零星的实时任务遵守M/C（内存计算）模型。我们提供了一个理论框架，其目的是在严格的特点可获得的可扩展性改进与单核系统上采用M/C任务模型。我们确定了一个紧的关键时刻M/C任务调度与固定的优先级，提供了一个精确的响应时间分析与伪多项式的复杂性。我们在我们的实验中表明，一个显着的可扩展性的改进，可以获得相对于经典的执行模型，放置一个重要的构建块设计更高效的分区多核系统。
A major obstacle towards the adoption of multi-core platforms for real-time systems is given by the difficulties in characterizing the interference due to memory contention. The simple fact that multiple cores may simultaneously access shared memory and communication resources introduces a significant pessimism in the timing and schedulability analysis. To counter this problem, predictable execution models have been proposed splitting task executions into two consecutive phases: a memory phase in which the required instruction and data are pre-fetched to local memory (M-phase), and an execution phase in which the task is executed with no memory contention (C-phase). Decoupling memory and execution phases not only simplifies the timing analysis, but it also allows a more efficient (and predictable) pipelining of memory and execution phases through proper co-scheduling algorithms. In this paper, we take a further step towards the design of smart co-scheduling algorithms for sporadic real-time tasks complying with the M/C (memory-computation) model. We provide a theoretical framework that aims at tightly characterizing the schedulability improvement obtainable with the adopted M/C task model on a single-core systems. We identify a tight critical instant for M/C tasks scheduled with fixed priority, providing an exact response-time analysis with pseudo-polynomial complexity. We show in our experiments that a significant schedulability improvement may be obtained with respect to classic execution models, placing an important building block towards the design of more efficient partitioned multi-core systems.
影响因子：
1.3
作者：
Davis, Robert I.;Burns, Alan
通讯作者：
Burns, Alan