2012 24th Euromicro Conference on Real-Time Systems最新文献_第3页

Replacement Policies for a Function-Based Instruction Memory: A Quantification of the Impact on Hardware Complexity and WCET Estimates 基于函数的指令存储器的替换策略:对硬件复杂性和WCET估计影响的量化

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.22

Stefan Metzlaff, T. Ungerer

引用次数: 5

Control-Quality Optimization for Distributed Embedded Systems with Adaptive Fault Tolerance 基于自适应容错的分布式嵌入式系统控制质量优化

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.40

Soheil Samii, Unmesh D. Bordoloi, P. Eles, Zebo Peng, A. Cervin

{"title":"Control-Quality Optimization for Distributed Embedded Systems with Adaptive Fault Tolerance","authors":"Soheil Samii, Unmesh D. Bordoloi, P. Eles, Zebo Peng, A. Cervin","doi":"10.1109/ECRTS.2012.40","DOIUrl":"https://doi.org/10.1109/ECRTS.2012.40","url":null,"abstract":"In this paper, we propose a design framework for distributed embedded control systems that ensures reliable execution and high quality of control even if some computation nodes fail. When a node fails, the configuration of the underlying distributed system changes and the system must adapt to this new situation by activating tasks at operational nodes. The task mapping as well as schedules and control laws that are customized for the new configuration influence the control quality and must, therefore, be optimized. The number of possible configurations due to faults is exponential in the number of nodes in the system. This design-space complexity leads to unaffordable design time and large memory requirements to store information related to mappings, schedules, and controllers. We demonstrate that it is sufficient to synthesize solutions for a small number of base and minimal configurations to achieve fault tolerance with an inherent minimum level of control quality. We also propose an algorithm to further improve control quality with a priority-based search of the set of configurations and trade-offs between task migration and replication.","PeriodicalId":425794,"journal":{"name":"2012 24th Euromicro Conference on Real-Time Systems","volume":"182 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133172311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Timing Analysis for Mode Switch in Component-Based Multi-mode Systems 基于组件的多模系统模式切换时序分析

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.23

Y. Hang, H. Hansson

引用次数: 14

Techniques Optimizing the Number of Processors to Schedule Multi-threaded Tasks 优化处理器数量以调度多线程任务的技术

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.37

Geoffrey Nelissen, V. Berten, J. Goossens, D. Milojevic

{"title":"Techniques Optimizing the Number of Processors to Schedule Multi-threaded Tasks","authors":"Geoffrey Nelissen, V. Berten, J. Goossens, D. Milojevic","doi":"10.1109/ECRTS.2012.37","DOIUrl":"https://doi.org/10.1109/ECRTS.2012.37","url":null,"abstract":"These last years, we have witnessed a dramatic increase in the number of cores available in computational platforms. Concurrently, a new coding paradigm dividing tasks into smaller execution instances called threads, was developed to take advantage of the inherent parallelism of multiprocessor platforms. However, only few methods were proposed to efficiently schedule hard real-time multi-threaded tasks on multiprocessor. In this paper, we propose techniques optimizing the number of processors needed to schedule such sporadic parallel tasks with constrained deadlines. We first define an optimization problem determining, for each thread, an intermediate (artificial) deadline minimizing the number of processors needed to schedule the whole task set. The scheduling algorithm can then schedule threads as if they were independent sequential sporadic tasks. The second contribution is an efficient and nevertheless optimal algorithm that can be executed online to determine the thread's deadlines. Hence, it can be used in dynamic systems were all tasks and their characteristics are not known a priori. We finally prove that our techniques achieve a resource augmentation bound of 2 when the threads are scheduled with algorithms such as U-EDF, PD2, LLREF, DP-Wrap, etc.","PeriodicalId":425794,"journal":{"name":"2012 24th Euromicro Conference on Real-Time Systems","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123263157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 93

Relaxing Mixed-Criticality Scheduling Strictness for Task Sets Scheduled with FP 用FP调度的任务集的混合临界调度松紧性

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.39

François Santy, L. George, P. Thierry, J. Goossens

{"title":"Relaxing Mixed-Criticality Scheduling Strictness for Task Sets Scheduled with FP","authors":"François Santy, L. George, P. Thierry, J. Goossens","doi":"10.1109/ECRTS.2012.39","DOIUrl":"https://doi.org/10.1109/ECRTS.2012.39","url":null,"abstract":"Current trends in the embedded systems field tend to collocate multiple functionalities upon a single computing platform, the aim being to reduce both the size and cost of embedded systems. Nevertheless, it is unlikely that all functionalities share the same level of criticality, and certification of the system has to be achieved using varying degrees of rigorousness. Typically, a task τi is guaranteed to meet its temporal constraints up to a criticality level that is equal to its own criticality. When those conditions are no longer met, i.e. when another higher priority task τj has its execution time that exceeds its Worst Case Execution Time (WCET) w.r.t. the criticality level of τi, a common approach is to suspend τi. However, in some cases, it may not be necessary to suspend tasks with a lower criticality immediately as they could still be executed without compromising the deadlines of high criticality tasks. As a step towards this aim, we propose a method, denoted Latest Completion Time (LCT), that allows lower criticality tasks to proceed with their execution as long as they do not prevent higher criticality tasks from meeting their deadlines. Furthermore, we show that tasks suspension can only be temporary, and prove that a particular definition of idle times can be used to reset the system's criticality level. Finally, we study the performances of our LCT mechanism w.r.t. the classical mechanism that suspends a task as soon as the system criticality level becomes higher than its own criticality.","PeriodicalId":425794,"journal":{"name":"2012 24th Euromicro Conference on Real-Time Systems","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129420365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 104

Generalized Fixed-Priority Scheduling with Limited Preemptions 有限抢占的广义固定优先级调度

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.34

R. J. Bril, M. V. D. Heuvel, U. Keskin, J. Lukkien

引用次数: 23

Outstanding Paper Award: Bounding and Shaping the Demand of Mixed-Criticality Sporadic Tasks 杰出论文奖:混合临界偶发任务需求的约束与塑造

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.24

Pontus Ekberg, W. Yi

引用次数: 142

Optimal Program Partitioning for Predictable Performance 可预测性能的最佳程序分区

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.18

J. Whitham, N. Audsley

{"title":"Optimal Program Partitioning for Predictable Performance","authors":"J. Whitham, N. Audsley","doi":"10.1109/ECRTS.2012.18","DOIUrl":"https://doi.org/10.1109/ECRTS.2012.18","url":null,"abstract":"Scratchpad memory (SPM) provides a predictable and energy efficient way to store program instructions and data. It would be ideal for embedded real-time systems if not for the practical difficulty that most programs have to be modified in source or binary form in order to use it effectively. This modification process is called partitioning, and it splits a large program into sub-units called regions that are small enough to be stored in SPM. Earlier papers on this subject have only considered regions formed around program structures, such as loops, methods and even entire tasks. Region formation and SPM allocation are performed in two separate steps. This is an approximation that does not make best use of SPM. In this paper, we propose a k-partitioning algorithm as a new way to solve the problem. This allows us to carry out region formation and SPM allocation simultaneously. We can generate optimal partitions for programs expressed either as call trees or by a restricted form of control-flow graph (CFG). We show that this approach obtains superior results to the previous two-step approach. We apply our algorithm to various programs and SPM sizes and show that it reduces the execution time cost for executing those programs relative to execution with cache.","PeriodicalId":425794,"journal":{"name":"2012 24th Euromicro Conference on Real-Time Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133970701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Deriving Monitoring Bounds for Distributed Real-Time Systems 分布式实时系统监控边界的推导

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.10

M. Neukirchner, S. Stein, R. Ernst

引用次数: 0

Partitioned Packing and Scheduling for Sporadic Real-Time Tasks in Identical Multiprocessor Systems 同一多处理机系统中零星实时任务的分区包装与调度

2012 24th Euromicro Conference on Real-Time Systems Pub Date : 2012-07-11 DOI: 10.1109/ECRTS.2012.43

Jian-Jia Chen, S. Chakraborty

{"title":"Partitioned Packing and Scheduling for Sporadic Real-Time Tasks in Identical Multiprocessor Systems","authors":"Jian-Jia Chen, S. Chakraborty","doi":"10.1109/ECRTS.2012.43","DOIUrl":"https://doi.org/10.1109/ECRTS.2012.43","url":null,"abstract":"Multiprocessor platforms have been widely adopted to accommodate the increasing computation requirement of modern applications. Partitioned scheduling (or packing) has been widely exploited by partitioning real-time tasks onto processors to meet the timing constraints, which has been shown to be NP-complete in the strong sense. This paper studies the approximation of partitioned scheduling by exploiting resource augmentation with (1) speeding up or (2) allocating more processors. When adopting speeding up to meet timing constraints, we provide a polynomial-time approximation scheme (PTAS) to derive near-optimal solutions only with the assumption that the ratio of the maximum relative deadline to the minimum relative deadline is a constant. The previously known PTAS for this problem imposes additional restrictions on the periods and the execution times of tasks. By removing these additional constraints, our scheme can be adopted for wider task sets. When considering the resource augmentation by allocating more processors, we show that there does not exist any asymptotic polynomial-time approximation scheme (APTAS) unless P=NP.","PeriodicalId":425794,"journal":{"name":"2012 24th Euromicro Conference on Real-Time Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124809941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 20