2015 27th Euromicro Conference on Real-Time Systems最新文献_第2页

Mixed-Criticality Scheduling on Multiprocessors Using Task Grouping 基于任务分组的多处理器混合临界调度

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.10

Jiankang Ren, L. T. Phan

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引用次数: 53

Cyclic Executives, Multi-core Platforms and Mixed Criticality Applications 循环执行器，多核平台和混合临界应用

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.8

A. Burns, Tom Fleming, Sanjoy Baruah

{"title":"Cyclic Executives, Multi-core Platforms and Mixed Criticality Applications","authors":"A. Burns, Tom Fleming, Sanjoy Baruah","doi":"10.1109/ECRTS.2015.8","DOIUrl":"https://doi.org/10.1109/ECRTS.2015.8","url":null,"abstract":"Historically safety-critical real-time systems have been implemented using a cyclic executive (CE). Here a series of frames (minor cycles) are executed in sequence. Once the series is complete the sequence is repeated. The duration of the full sequence is often known as the major cycle. Within each frame, units of computation (jobs) are executed, again in sequence. Although there are a number of drawbacks to the use of CEs they have the advantage of being fully deterministic and efficiently implemented. For multi-core platforms, running a set of frames on each core is an obvious extension to the single core approach. Here there is advantage in coordinating the execution of the cores so that frames are released at the same time across all cores. For mixed criticality systems, the requirement for separation would imply that, at any time, code of the same criticality must execute on all cores. In this paper we consider how this requirement can be met and the performance, in terms of schedulability, it delivers. We consider partitioned and globally allocated work. For partitioned systems an allocation scheme is developed. For globally scheduled schemes we develop a polynomial-time sufficient schedulability test that determines whether a given mixed-criticality system is schedulable, and constructs a schedule if it is.","PeriodicalId":243434,"journal":{"name":"2015 27th Euromicro Conference on Real-Time Systems","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114554393","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: 25

Supporting Component-Based Development in Partitioned Multiprocessor Real-Time Systems 支持基于组件的分区多处理器实时系统开发

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.31

Alessandro Biondi, G. Buttazzo, M. Bertogna

引用次数: 17

An Optimal Semi-partitioned Scheduler for Uniform Heterogeneous Multiprocessors 统一异构多处理器的最优半分区调度程序

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.25

Kecheng Yang, James H. Anderson

引用次数: 5

Feasibility Analysis of Engine Control Tasks under EDF Scheduling EDF调度下发动机控制任务的可行性分析

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.20

Alessandro Biondi, G. Buttazzo, S. Simoncelli

{"title":"Feasibility Analysis of Engine Control Tasks under EDF Scheduling","authors":"Alessandro Biondi, G. Buttazzo, S. Simoncelli","doi":"10.1109/ECRTS.2015.20","DOIUrl":"https://doi.org/10.1109/ECRTS.2015.20","url":null,"abstract":"Engine control applications include software tasks that are triggered at predetermined angular values of the crankshaft, thus generating a computational workload that varies with the engine speed. To avoid overloads at high rotation speeds, these tasks are implemented to self adapt and reduce their computational demand by switching mode at given rotation speeds. For this reason, they are referred to as adaptive variable rate (AVR) tasks. Although a few works have been proposed in the literature to model and analyze the schedulability of such a peculiar type of tasks, an exact analysis of engine control applications has been derived only for fixed priority systems, under a set of simplifying assumptions. The major problem of scheduling AVR tasks with fixed priorities, however, is that, due to engine accelerations, the interarrival period of an AVR task is subject to large variations, therefore there will be several speeds at which any fixed priority assignment is far from being optimal, significantly penalizing the schedulability of the system. This paper proposes for the first time an exact feasibility test under the Earliest Deadline First scheduling algorithm for tasks sets including regular periodic tasks and AVR tasks triggered by a common rotation source. In addition, a set of simulation results are reported to evaluate the schedulability gain achieved in this context by EDF over fixed priority scheduling.","PeriodicalId":243434,"journal":{"name":"2015 27th Euromicro Conference on Real-Time Systems","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125208813","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: 29

Integration of Cache Partitioning and Preemption Threshold Scheduling to Improve Schedulability of Hard Real-Time Systems 集成缓存分区和抢占阈值调度以提高硬实时系统的可调度性

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.14

Chao Wang, Z. Gu, Haibo Zeng

引用次数: 11

Probabilistic Response Time and Joint Analysis of Periodic Tasks 周期任务的概率响应时间与联合分析

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.28

Bogdan Tanasa, Unmesh D. Bordoloi, P. Eles, Zebo Peng

引用次数: 21

An Efficient Method for Assigning Harmonic Periods to Hard Real-Time Tasks with Period Ranges 具有周期范围的硬实时任务谐波周期分配的有效方法

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.21

M. Nasri, G. Fohler

{"title":"An Efficient Method for Assigning Harmonic Periods to Hard Real-Time Tasks with Period Ranges","authors":"M. Nasri, G. Fohler","doi":"10.1109/ECRTS.2015.21","DOIUrl":"https://doi.org/10.1109/ECRTS.2015.21","url":null,"abstract":"During the design phase of many real-time systems, designers often have a range of acceptable period values for which some levels of safety or quality of service are guaranteed. The choice of period values influences system schedulability and computational complexity of schedulability analysis, especially for the rate monotonic (RM) scheduling algorithm. It has been shown that RM guarantees 100% utilization if the periods are harmonic, i.e., Each period is an integer multiple of shorter periods. In this paper, we address harmonic period assignment problem where each task has a given period range. We extend the results of our previous work and present an O(n^2log(n)) algorithm (where n is the number of tasks) to verify necessary and sufficient conditions for the existence of a harmonic period assignment in cases where the previous solution has pseudo-polynomial computational complexity. We provide utilization bounds of the potential assignments as well as a heuristic algorithm to construct low utilization harmonic task sets. The efficiency of our period assignment algorithms has been evaluated in terms of acceptance ratio, task set utilization, data structure size, and the number of operations required for harmonic period assignment.","PeriodicalId":243434,"journal":{"name":"2015 27th Euromicro Conference on Real-Time Systems","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114148577","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: 31

Average and Worst-Case Latency Improvements in Mixed-Criticality Wormhole Networks-on-Chip 片上混合临界虫洞网络的平均和最坏情况延迟改进

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.12

L. Indrusiak, J. Harbin, A. Burns

引用次数: 43

Worst-Case Energy Consumption Analysis for Energy-Constrained Embedded Systems 能量约束嵌入式系统的最坏情况能耗分析

2015 27th Euromicro Conference on Real-Time Systems Pub Date : 2015-07-08 DOI: 10.1109/ECRTS.2015.17

Peter Wägemann, T. Distler, Timo Hönig, Heiko Janker, R. Kapitza, Wolfgang Schröder-Preikschat

{"title":"Worst-Case Energy Consumption Analysis for Energy-Constrained Embedded Systems","authors":"Peter Wägemann, T. Distler, Timo Hönig, Heiko Janker, R. Kapitza, Wolfgang Schröder-Preikschat","doi":"10.1109/ECRTS.2015.17","DOIUrl":"https://doi.org/10.1109/ECRTS.2015.17","url":null,"abstract":"The fact that energy is a scarce resource in many embedded real-time systems creates the need for energy-aware task schedulers, which not only guarantee timing constraints but also consider energy consumption. Unfortunately, existing approaches to analyze the worst-case execution time (WCET) of a task usually cannot be directly applied to determine its worst-case energy consumption (WCEC) due to execution time and energy consumption not being closely correlated on many state-of-the-art processors. Instead, a WCEC analyzer must take into account the particular energy characteristics of a target platform. In this paper, we present 0g, a comprehensive approach to WCEC analysis that combines different techniques to speed up the analysis and to improve results. If detailed knowledge about the energy costs of instructions on the target platform is available, our tool is able to compute upper bounds for the WCEC by statically analyzing the program code. Otherwise, a novel approach allows 0g to determine the WCEC by measurement after having identified a set of suitable program inputs based on an auxiliary energy model, which specifies the energy consumption of instructions in relation to each other. Our experiments for three target platforms show that 0g provides precise WCEC estimates.","PeriodicalId":243434,"journal":{"name":"2015 27th Euromicro Conference on Real-Time Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130464702","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: 41