TypicalCPA - Typical Worst Case Compositional Performance Analysis

控制工程和通信技术中的许多应用对有限数量的截止日期错过是鲁棒的。这种鲁棒性可以用于嵌入式系统的有效尺寸。然而，需要对定时行为进行正式验证，以检查最后期限错过的最大频率。实现这一验证任务是目前项目的主题：对于复杂的嵌入式系统与异构组件所谓的（m，k）-保证应正式派生。（m，k）-保证表明k个连续执行中不超过m个受到截止日期错过的影响。在当前的项目中，我们努力深入了解瞬态过载系统的行为。在项目的第一阶段，在将现有的单组件（m，k）验证方法集成到现有的组合性能分析（CPA）框架之前，对该方法进行了显着改进。为此，各个组件分析之间的耦合机制逐渐扩展到“典型最差情况组合性能分析（TypicalCPA）”。实际可用的系统分析仍然缺少的是过载事件模型的有效传播和端到端度量的推导。然后，将结果用于开发（m，k）系统设计。在新阶段的第一步中，应优化耦合机制的计算，以提高（m，k）保证的精度。组件相关分析的耦合是由系统中的激活事件流引起的。我们要考虑这样一个事实，即激活事件的性质在通过系统传播时会发生变化，因此-取决于时间和地点-它是否是过载的原因。所获得的结果将允许调查的空间和时间的传播系统中的过载。随后，在考虑各种激活语义的情况下，端到端系统度量的定义和计算将被推进。这包括计算相对数据年龄的变化和由于（m，k）损失而导致的系统中相对数据年龄的分散。此外，还应优化系统设计，以实现（m，k）-保证要求。对所获得结果的详细评估应基于工业案例研究，并继续关注以太网骨干网络以及综合测试案例，其中应提供关于自动生成具有瞬态过载行为的测试系统的新结果。

Numerous applications in control engineering and communication technology are robust towards a limited number of deadline misses. This robustness can be exploited for the efficient dimensioning of embedded systems. However, a formal verification of the timing behavior is required, which checks the maximum frequency of deadline misses. Realizing this verification task is subject of the current project: For complex embedded systems with heterogeneous components so called (m,k)-guarantees shall be formally derived. The (m,k)-guarantees indicate that no more than m out of k consecutive executions are affected by a deadline miss. In the current project, we strive to gain an in-depth understanding of the behavior of transiently overloaded systems.In the first project phase the available single component (m,k)-verification method was significantly improved before it was integrated in the existing Compositional Performance Analysis (CPA) framework. For this purpose, the coupling mechanisms between the individual component analyses were gradually extended to a „Typical Worst Case Compositional Performance Analysis (TypicalCPA)“.What is still missing towards a practically usable system analysis is the efficient propagation of event models with overload and the derivation of end-to-end metrics. The results shall, then, be used to develop an (m,k) system design. In the first step of the new phase, the computation of the coupling mechanisms shall be optimized, in order to increase the accuracy of the (m,k)-guarantees. The coupling of component-related analyses results from the flow of activation events through the system. We want to consider the fact that the nature of an activation event can change while being propagated through the system, such that - depending on time and place – it is cause of overload or not. The obtained results will allow investigating the spatial and temporal propagation of overload in the system. Subsequently, the definition and computation of end-to-end system metrics under consideration of various activation semantics shall be advanced. This includes computing the change of the relative data age and the dispersion of the relative data age in the system due to (m,k)-losses. Moreover, the system design shall be optimized, such that demanding (m,k)-guarantees can be realized.The concluding detailed evaluation of the obtained results shall be based on industrial case studies, with a continued focus on Ethernet-backbone networks, as well as on synthetic test cases, where new results shall be provided with respect to the automatic generation of test systems with transient overload behavior.