Results 1 - 10
of
15
An interface algebra for real-time components.”
- in IEEE RealTime and Embedded Technology and Applications Symposium (RTAS),
, 2006
"... Abstract We present an assume-guarantee interface algebra for real - ..."
Abstract
-
Cited by 34 (2 self)
- Add to MetaCart
(Show Context)
Abstract We present an assume-guarantee interface algebra for real -
Real-time interfaces for composing real-time systems
- In EMSOFT
, 2006
"... Recently, a number of frameworks were proposed to extend interface theory to the domains of single-processor and distributed real-time systems. This paper unifies some of these approaches and proves properties like refinement and independent implementability. We also explicitly state the requirement ..."
Abstract
-
Cited by 29 (1 self)
- Add to MetaCart
(Show Context)
Recently, a number of frameworks were proposed to extend interface theory to the domains of single-processor and distributed real-time systems. This paper unifies some of these approaches and proves properties like refinement and independent implementability. We also explicitly state the requirements to a framework for these properties to be fulfilled. Further, a new notion of adaptive interfaces is introduced that supports the design by providing mechanisms for propagating system constraints, such as (end-to-end) delays, available computing and communication resources, buffer spaces, and energy. Guarantees and assumptions on interfaces are not any longer static but adapt according to the system environment. This can be used to answer synthesis questions at design time or to adapt system parameters to changing environment requirements at run-time. The applicability of the presented framework is proven by adapting it to a number of different real-time analysis models.
Load balancing techniques for distributed stream processing applications in overlay environments
- In: Proceedings of the 9th International Symposium on Object and Component-Oriented Real-Time Distributed Computing, ISORC, Gyeongju, Korea
, 2006
"... Service overlays that support distributed stream processing applications are increasingly being deployed in wide-area environments. The inherent heterogeneous, dynamic and large-scale nature of these systems makes it difficult to meet the Quality of Service (QoS) requirements of the distributed stre ..."
Abstract
-
Cited by 11 (8 self)
- Add to MetaCart
(Show Context)
Service overlays that support distributed stream processing applications are increasingly being deployed in wide-area environments. The inherent heterogeneous, dynamic and large-scale nature of these systems makes it difficult to meet the Quality of Service (QoS) requirements of the distributed stream processing applications. In this paper we address the load balancing problem for distributed stream processing applications and present a decentralized and adaptive algorithm that allows the composition of distributed stream processing applications on the fly across a large-scale system, while satisfying their QoS demands. The algorithm fairly distributes the load on the resources and adapts dynamically to changes in the resource utilization or the QoS requirements of the applications. Our experimental results demonstrate the scalability, efficiency and performance of our approach. 1
Compadres: A Lightweight Component Middleware Framework for Composing Distributed, Real-Time, Embedded Systems with Real-Time Java
- In Proc. ACM/IFIP/USENIX 8th Int’l Middleware Conference (Middleware 2007
"... Abstract. Component frameworks simplify development of enterprise systems and enable code reuse, but most frameworks are unpredictable and hence unsuitable for embedded or real-time systems. Similarly, Java is increasingly being used to build embedded system software because of its portability and ..."
Abstract
-
Cited by 4 (0 self)
- Add to MetaCart
Abstract. Component frameworks simplify development of enterprise systems and enable code reuse, but most frameworks are unpredictable and hence unsuitable for embedded or real-time systems. Similarly, Java is increasingly being used to build embedded system software because of its portability and ease of use. The Real-Time Specification for Java (RTSJ) reduces the unpredictability in Java execution times by eliminating the need for a garbage collector. However, it introduces programming complexity that makes it difficult to build non-trivial applications. To bring the advantages of Java component development to DRE systems, while simultaneously simplifying the use of RTSJ, therefore, we have developed a new lightweight component model for RTSJ called Compadres. Compadres offers the following advantages: 1) Simple component definition in Java that abstracts away RTSJ memory management complexity; 2) System assembly from components by connecting ports that communicate through strongly-typed objects; 3) The Compadres compiler that automatically generates the scoped memory architecture for components, while the component framework handles communication between the components. To validate this work, we construct a nontrivial example application using the component framework, a simple real-time CORBA implementation. We then analyze the performance and efficiency of our component example versus a non-component example, RTZen. Our measurements show that our Compadres example built with components incurs only minor time overhead as compared to a comparable hand-coded example.
RASC: Dynamic Rate Allocation for Distributed Stream Processing Applications
"... In today’s world, stream processing systems have become important, as applications like media broadcasting, sensor network monitoring and on-line data analysis increasingly rely on real-time stream processing. In this paper, we propose a distributed stream processing system that composes stream proc ..."
Abstract
-
Cited by 3 (1 self)
- Add to MetaCart
(Show Context)
In today’s world, stream processing systems have become important, as applications like media broadcasting, sensor network monitoring and on-line data analysis increasingly rely on real-time stream processing. In this paper, we propose a distributed stream processing system that composes stream processing applications dynamically, while meeting their rate demands. Our system consists of the following components: (1) a distributed component discovery algorithm that discovers components available at nodes on demand, (2) resource monitoring techniques to maintain current resource availability information, (3) a scheduling algorithm that schedules application execution, and (4) a minimum cost composition algorithm that composes applications dynamically based on component and resource availability and scheduling demands. Our detailed experimental results, over the PlanetLab testbed, demonstrate the performance and efficiency of our approach. 1
Accommodating Bursts in Distributed Stream Processing Systems
"... Stream processing systems have become important, as applications like media broadcasting, sensor network monitoring and on-line data analysis increasingly rely on realtime stream processing. Such systems are often challenged by the bursty nature of the applications. In this paper, we present BARRE ( ..."
Abstract
-
Cited by 3 (2 self)
- Add to MetaCart
(Show Context)
Stream processing systems have become important, as applications like media broadcasting, sensor network monitoring and on-line data analysis increasingly rely on realtime stream processing. Such systems are often challenged by the bursty nature of the applications. In this paper, we present BARRE (Burst Accommodation through Rate REconfiguration), a system to address the problem of bursty data streams in distributed stream processing systems. Upon the emergence of a burst, BARRE dynamically reserves resources dispersed across the nodes of a distributed stream processing system, based on the requirements of each application as well as the resources available on the nodes. Our experimental results over our Synergy distributed stream processing system demonstrate the efficiency of our approach. 1.
A Component Framework for Real-time Java ∗
"... The Real-time Specification for Java (RTSJ) offers predictable memory management and scheduling required for real-time applications. However, the usage of its memory model is difficult for standard Java developers, who are accustomed to automatic memory management. Components offer the opportunity t ..."
Abstract
-
Cited by 2 (1 self)
- Add to MetaCart
(Show Context)
The Real-time Specification for Java (RTSJ) offers predictable memory management and scheduling required for real-time applications. However, the usage of its memory model is difficult for standard Java developers, who are accustomed to automatic memory management. Components offer the opportunity to hide the complexities of the RTSJ’s memory model, in addition to benefits such as reusability and modularity. To this end, we propose a component framework that brings together the ease of programming in Java and the predictability of RTSJ. 1
Resource Management using Pattern-based Prediction to Address Bursty Data Streams
"... Abstract—In the recent years we have witnessed a prolif-eration of distributed stream processing systems that need to operate efficiently, even when data bursts occur. Examples include road traffic networks, processing of financial feeds, network monitoring and real-time sensor data analysis systems ..."
Abstract
-
Cited by 1 (1 self)
- Add to MetaCart
(Show Context)
Abstract—In the recent years we have witnessed a prolif-eration of distributed stream processing systems that need to operate efficiently, even when data bursts occur. Examples include road traffic networks, processing of financial feeds, network monitoring and real-time sensor data analysis systems. An im-portant challenge in managing these systems is effective resource management and meeting the QoS demands of the stream processing applications under different workload conditions, even under bursts. In this paper we present our approach that aims to predict the execution times of the distributed stream processing applications by taking into account the effects of the bursts and what is the typical workload of the stream processing system. Our approach builds application data rate patterns at run-time and predicts the effect of the burst on the performance of the applications, to identify whether there is a need to react on the onset of a burst. Our detailed experimental results over our Synergy middleware illustrate that our approach is practical, depicts good performance and has low resource overhead. I.
Autonomic Mechanisms for the Automotive Industry
, 2007
"... Automotive systems are continuously facing an increase of complex and evolving software requirements. AUTOSAR appeared as a standard solution that allows seamless integration and provides better performance than the current proprietary infrastructures. However, it still requires significant efforts ..."
Abstract
- Add to MetaCart
Automotive systems are continuously facing an increase of complex and evolving software requirements. AUTOSAR appeared as a standard solution that allows seamless integration and provides better performance than the current proprietary infrastructures. However, it still requires significant efforts in manual configuration and management of software deployments. Autonomic computing is considered a feasible solution to handle all the technical issues arisen by the emerging challenges of the automotive industry. This document shows some of the insufficiencies that AUTOSAR suffers to cope with this novel challenges and proposes the use of some techniques and methods that could help in purpose of creating a vehicle self-managed system. Special thanks for all the people that helped in the process of writing this thesis:
