Download or read book Dynamic Scheduling of Real time Tasks written by Babak Hamidzadeh and published by . This book was released on 1993 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Deadline Scheduling for Real Time Systems written by John A. Stankovic and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many real-time systems rely on static scheduling algorithms. This includes cyclic scheduling, rate monotonic scheduling and fixed schedules created by off-line scheduling techniques such as dynamic programming, heuristic search, and simulated annealing. However, for many real-time systems, static scheduling algorithms are quite restrictive and inflexible. For example, highly automated agile manufacturing, command, control and communications, and distributed real-time multimedia applications all operate over long lifetimes and in highly non-deterministic environments. Dynamic real-time scheduling algorithms are more appropriate for these systems and are used in such systems. Many of these algorithms are based on earliest deadline first (EDF) policies. There exists a wealth of literature on EDF-based scheduling with many extensions to deal with sophisticated issues such as precedence constraints, resource requirements, system overload, multi-processors, and distributed systems. Deadline Scheduling for Real-Time Systems: EDF and Related Algorithms aims at collecting a significant body of knowledge on EDF scheduling for real-time systems, but it does not try to be all-inclusive (the literature is too extensive). The book primarily presents the algorithms and associated analysis, but guidelines, rules, and implementation considerations are also discussed, especially for the more complicated situations where mathematical analysis is difficult. In general, it is very difficult to codify and taxonomize scheduling knowledge because there are many performance metrics, task characteristics, and system configurations. Also, adding to the complexity is the fact that a variety of algorithms have been designed for different combinations of these considerations. In spite of the recent advances there are still gaps in the solution space and there is a need to integrate the available solutions. For example, a list of issues to consider includes: preemptive versus non-preemptive tasks, uni-processors versus multi-processors, using EDF at dispatch time versus EDF-based planning, precedence constraints among tasks, resource constraints, periodic versus aperiodic versus sporadic tasks, scheduling during overload, fault tolerance requirements, and providing guarantees and levels of guarantees (meeting quality of service requirements). Deadline Scheduling for Real-Time Systems: EDF and Related Algorithms should be of interest to researchers, real-time system designers, and instructors and students, either as a focussed course on deadline-based scheduling for real-time systems, or, more likely, as part of a more general course on real-time computing. The book serves as an invaluable reference in this fast-moving field.

Download or read book Architecture and Design of Distributed Embedded Systems written by Bernd Kleinjohann and published by Springer. This book was released on 2013-04-18 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the decreasing production costs of IT systems, applications that had to be realised as expensive PCBs formerly, can now be realised as a system-on-chip. Furthermore, low cost broadband communication media for wide area communication as well as for the realisation of local distributed systems are available. Typically the market requires IT systems that realise a set of specific features for the end user in a given environment, so called embedded systems. Some examples for such embedded systems are control systems in cars, airplanes, houses or plants, information and communication devices like digital TV, mobile phones or autonomous systems like service- or edutainment robots. For the design of embedded systems the designer has to tackle three major aspects: The application itself including the man-machine interface, The (target) architecture of the system including all functional and non-functional constraints and, the design methodology including modelling, specification, synthesis, test and validation. The last two points are a major focus of this book. This book documents the high quality approaches and results that were presented at the International Workshop on Distributed and Parallel Embedded Systems (DIPES 2000), which was sponsored by the International Federation for Information Processing (IFIP), and organised by IFIP working groups WG10.3, WG10.4 and WG10.5. The workshop took place on October 18-19, 2000, in Schloß Eringerfeld near Paderborn, Germany. Architecture and Design of Distributed Embedded Systems is organised similar to the workshop. Chapters 1 and 4 (Methodology I and II) deal with different modelling and specification paradigms and the corresponding design methodologies. Generic system architectures for different classes of embedded systems are presented in Chapter 2. In Chapter 3 several design environments for the support of specific design methodologies are presented. Problems concerning test and validation are discussed in Chapter 5. The last two chapters include distribution and communication aspects (Chapter 6) and synthesis techniques for embedded systems (Chapter 7). This book is essential reading for computer science researchers and application developers.

Download or read book Flexible and Dynamic Scheduling of Generalized Tasks in Real time Systems written by Syed Muhammad Raza Rizvi and published by . This book was released on 1996 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scheduling in Real Time Systems written by Francis Cottet and published by Wiley. This book was released on 2002-11-22 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: * Real-time systems are used in a wide range of applications, including command and control systems, flight control, telecommunication systems, and online purchase payment * Provides an accessible yet comprehensive treatment * of real-time computing and communications systems * Outlines the basics of real-time scheduling and scheduling policies designed for real-time applications * Each chapter contains examples and case studies along with test exercises and solutions

Download or read book Feedback based Task Scheduling in Real time Systems written by Suzhen Lin and published by . This book was released on 2005 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Real-time computing is an enabling technology for many current and next generation applications. One of the key components of real-time systems is the scheduling of tasks, the objective of which is to meet task deadlines predictably. Traditional real-time task scheduling paradigms perform well in static or dynamic systems in which the workload can be accurately modeled. Unfortunately, in many complex applications, unpredictable dynamic factors exist due to which precise workload characterization is difficult. In recent years, feedback control techniques have been successfully applied to address the issue of unpredictable workload in computing systems. In this dissertation, we develop feedback-based algorithms and analysis for some important dynamic scheduling problems in real-time systems. First, we address the problem of selective herbicide spraying in precision farming application. The goal is to achieve low weed miss ratio and high CPU utilization. We carry out system identification, vehicle modeling and controller design. In our design, the requested CPU utilization is fed back and the vehicle speed is controlled. The system model is verified and performance evaluation is carried out through simulation studies. The second problem is task scheduling based on (m, k)-firm deadline constraints in real-time systems. The proposed solution feeds back the current dynamic failure rate (DFR) and adjusts the task's QoS based on DFR on-line. We also propose a novel fairness metric to evaluate the fairness in QoS among tasks achieved by the scheduler. The simulation results show that the QoS of tasks can be improved significantly while keeping the DFR below a certain threshold. The third problem is combined task scheduling with fault tolerance in real-time systems. In our model, the rate monotonic scheduling algorithm and deferrable server algorithm are used to schedule periodic and aperiodic tasks, respectively. By using feedback control technique, we adjust the capacity of the deferrable servers based on the failure rate of the periodic tasks. The performances of the systems are evaluated through simulation studies. The last problem is task scheduling in distributed real-time systems. We propose a double-loop scheme to keep the deadline miss ratio close to the set point and maximize the CPU utilization, and analyze the stability of the system in Z-domain. We also propose a global scheduling method to achieve load balancing by using a suitable load index. The performances of the systems are evaluated through simulation studies. The feedback-based solutions proposed in this dissertation are based on the principle of controlling the trade-off between deadline miss ratio and resource utilization. This idea can be adapted not only to other scheduling problems in real-time systems, but also to scheduling problems in non-real-time systems.

Download or read book Dynamic Scheduling Algorithms for Distributed Soft Real time Systems written by Hung-Yang Chang and published by . This book was released on 1987 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Scheduling of Hard Real time Applications in Open Systems Environment written by Zhong Deng and published by . This book was released on 1996 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "This paper focuses on the problem of providing run- time support to real-time applications and non-real-time applications in an open system. It describes a two-level hierarchical priority-driven scheme for scheduling independently developed applications. The scheme allows the developer of each real-time application to validate the schedulability of the application independently of other applications. Once a real-time application is created and accepted by the open system, its schedulability is guaranteed regardless of the behaviors of other applications that execute concurrently in the system."

Download or read book Hard Real Time Computing Systems written by Giorgio C Buttazzo and published by Springer Science & Business Media. This book was released on 2011-09-10 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: This updated edition offers an indispensable exposition on real-time computing, with particular emphasis on predictable scheduling algorithms. It introduces the fundamental concepts of real-time computing, demonstrates the most significant results in the field, and provides the essential methodologies for designing predictable computing systems used to support time-critical control applications. Along with an in-depth guide to the available approaches for the implementation and analysis of real-time applications, this revised edition contains a close examination of recent developments in real-time systems, including limited preemptive scheduling, resource reservation techniques, overload handling algorithms, and adaptive scheduling techniques. This volume serves as a fundamental advanced-level textbook. Each chapter provides basic concepts, which are followed by algorithms, illustrated with concrete examples, figures and tables. Exercises and solutions are provided to enhance self-study, making this an excellent reference for those interested in real-time computing for designing and/or developing predictable control applications.

Download or read book Closed loop Dynamic Scheduling for Real time Tracking written by Min Young Nam and published by . This book was released on 2006 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Real-time tracking is a task that can be used for all sorts of valuable location aware services and applications. As the speed of processors and the accuracy of sensors have improved, we now live in a world where people and objects can be tracked very accurately in real-time. The quality of real-time tracking depends on a lot of factors such as the sensor's accuracy, sensor speed, tracking algorism etc. Still if we don't schedule the sensing tasks well enough, we would not be using the all the sensing resources to its full potential. This thesis discusses about the improvement of real-time tracking using closed-loop dynamic scheduling methods. A traditional scheduler normally just schedule jobs according to a predetermined way. Because of the nature of real-time tracking, we can not expect what will happen. Thus, it is more efficient to use a closed-loop dynamic scheduling method which gets feed-back data such as the location, speed, direction of the target and adaptively adjusts so that we would achieve the required tracking performance. Then we can guarantee a certain level of certainty of the tracking task performance and perform services that require that quality level of tracking accuracy. This thesis uses two distinct applications to develop and test the performance of two scheduling methods which dynamically change in nature, using feedback information from the tracking tasks. This will strengthen the importance of closed-loop dynamic scheduling for real-time tracking. The first application is an indoor tracking of human and small objects using multiple sensors while the second is an outdoor tracking of aircrafts, missiles, or any vehicles that can be sensed with a radar.

Download or read book Time critical Multirate Scheduling Using Contemporary Real time Operating System Services written by Dave E. Eckhardt and published by . This book was released on 1983 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Scheduling for Real Time Systems written by Apurva Shah and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiprocessor Scheduling for Real Time Systems written by Sanjoy Baruah and published by Springer. This book was released on 2015-01-02 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of both theoretical and pragmatic aspects of resource-allocation and scheduling in multiprocessor and multicore hard-real-time systems. The authors derive new, abstract models of real-time tasks that capture accurately the salient features of real application systems that are to be implemented on multiprocessor platforms, and identify rules for mapping application systems onto the most appropriate models. New run-time multiprocessor scheduling algorithms are presented, which are demonstrably better than those currently used, both in terms of run-time efficiency and tractability of off-line analysis. Readers will benefit from a new design and analysis framework for multiprocessor real-time systems, which will translate into a significantly enhanced ability to provide formally verified, safety-critical real-time systems at a significantly lower cost.

Download or read book Foundations of Real Time Computing Scheduling and Resource Management written by André M. van Tilborg and published by Springer Science & Business Media. This book was released on 1991-07-31 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains a selection of papers that focus on the state-of the-art in real-time scheduling and resource management. Preliminary versions of these papers were presented at a workshop on the foundations of real-time computing sponsored by the Office of Naval Research in October, 1990 in Washington, D.C. A companion volume by the title Foundations of Real-Time Computing: Fonnal Specifications and Methods complements this book by addressing many of the most advanced approaches currently being investigated in the arena of formal specification and verification of real-time systems. Together, these two texts provide a comprehensive snapshot of current insights into the process of designing and building real-time computing systems on a scientific basis. Many of the papers in this book take care to define the notion of real-time system precisely, because it is often easy to misunderstand what is meant by that term. Different communities of researchers variously use the term real-time to refer to either very fast computing, or immediate on-line data acquisition, or deadline-driven computing. This text is concerned with the very difficult problems of scheduling tasks and resource management in computer systems whose performance is inextricably fused with the achievement of deadlines. Such systems have been enabled for a rapidly increasing set of diverse end-uses by the unremitting advances in computing power per constant-dollar cost and per constant-unit-volume of space. End-use applications of deadline-driven real-time computers span a spectrum that includes transportation systems, robotics and manufacturing, aerospace and defense, industrial process control, and telecommunications.

Download or read book Task Scheduling and Communication Support for Parallel and Distributed Real time Systems written by Jong-Pyng Li and published by . This book was released on 1993 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Scheduling with Microsoft Project 2010 written by Rodolfo Ambriz and published by J. Ross Publishing. This book was released on 2011-05-15 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through the use of best practices, helpful screen shots, hands-on exercises, and review questions, this book instructs you on how to build dynamic schedules with Microsoft Project 2010 that will allow you to explore 'what if?' scenarios and decrease the time you spend making static schedule changes.

Download or read book Real Time Systems written by Rajib Mall and published by Pearson Education India. This book was released on 2009-05 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The presence and use of real-time systems is becoming increasingly common. Examples of such systems range from nuclear reactors, to automotive controllers, and also entertainment software such as games and graphics animation. The growing importance of rea.