The HPC-DAG Task Model for Heterogeneous Real-Time Systems
The HPC-DAG Task Model for Heterogeneous Real-Time Systems
复制标题
异构实时系统的 HPC-DAG 任务模型
DOI：
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发表时间：
2020
影响因子：
3.7
通讯作者：
M. Bertogna
中科院分区：
文献类型：
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作者：
Zahaf Houssam;Nicola Capodieci;R. Cavicchioli;Giuseppe Lipari;M. Bertogna
最新的嵌入式实时系统商业硬件平台在同一片上系统上具有异构处理单元和计算加速器。在为此类架构设计复杂的实时应用程序时，设计人员面临许多困难的选择，例如决定使用哪个计算引擎来执行特定任务，或者对给定功能采用何种程度的并行性。为了帮助设计人员探索广阔的设计选择空间并调整调度参数，我们提出了一种新颖的实时应用程序模型，称为 HPC-DAG（异构并行条件定向非循环图模型），专门针对异构平台而设计。 HPC-DAG 允许系统设计者为不同的处理引擎指定软件组件的替代实现，以及对 if-then-else 语句进行建模的条件分支。我们还提出了 HPC-DAG 模型的可调度性分析和一组启发式分配算法，旨在提高延迟敏感应用程序的可调度性。我们的分析考虑了抢占任务的成本，这在某些处理器上是不可忽略的。我们展示了我们的方法在实际案例研究中的使用，并通过将其与文献中先前提出的最先进算法进行比较来证明其有效性。
Recent commercial hardware platforms for embedded real-time systems feature heterogeneous processing units and computing accelerators on the same System-on-Chip. When designing complex real-time applications for such architectures, the designer is exposed to a number of difficult choices, like deciding on which compute engine to execute a certain task, or what degree of parallelism to adopt for a given function. To help the designer exploring the wide space of design choices and tune the scheduling parameters, we propose a novel real-time application model, called HPC-DAG (Heterogeneous Parallel Condition Directed Acyclic Graph Model), specifically conceived for heterogeneous platforms. An HPC-DAG allows the system designer to specify alternative implementations of a software component for different processing engines, as well as conditional branches to model if-then-else statements. We also propose a schedulability analysis for the HPC-DAG model and a set of heuristic allocation algorithms aimed at improving schedulability for latency sensitive applications. Our analysis takes into account the cost of preempting a task, which can be non-negligible on certain processors. We show the use of our approach on a realistic case study, and we demonstrate its effectiveness by comparing it with state-of-the-art algorithms previously proposed in literature.