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

End-To-End Deadlines over Dynamic Topologies 动态拓扑的端到端截止日期

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-08 DOI: 10.4230/LIPIcs.ECRTS.2019.10

Victor Millnert, J. Eker, Enrico Bini

引用次数: 3

PREM-Based Optimal Task Segmentation Under Fixed Priority Scheduling 固定优先级调度下基于prem的最优任务分割

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-08 DOI: 10.4230/LIPIcs.ECRTS.2019.4

M. R. Soliman, R. Pellizzoni

引用次数: 18

Implementation of Memory Centric Scheduling for COTS Multi-Core Real-Time Systems 面向COTS多核实时系统的内存中心调度实现

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-02 DOI: 10.4230/LIPICS.ECRTS.2019.7

J. Rivas, J. Goossens, Xavier Poczekajlo, Antonio Paolillo

{"title":"Implementation of Memory Centric Scheduling for COTS Multi-Core Real-Time Systems","authors":"J. Rivas, J. Goossens, Xavier Poczekajlo, Antonio Paolillo","doi":"10.4230/LIPICS.ECRTS.2019.7","DOIUrl":"https://doi.org/10.4230/LIPICS.ECRTS.2019.7","url":null,"abstract":"The demands for high performance computing with a low cost and low power consumption are driving a transition towards multi-core processors in many consumer and industrial applications. However, the adoption of multi-core processors in the domain of real-time systems faces a series of challenges that has been the focus of great research intensity during the last decade. These challenges arise in great part from the non real-time nature of the hardware arbiters that schedule the access to shared resources, such as the main memory. One solution proposed in the literature is called Memory Centric Scheduling, which defines a separate software scheduler for the sections of the tasks that will access the main memory, hence circumventing the low level unpredictable hardware arbiters. Several Memory Centric schedulers and associated theoretical analyses have been proposed, but as far as we know, no actual implementation of the required OS-level underpinnings to support dynamic event-driven Memory Centric Scheduling has been presented before. In this paper we aim to fill this gap, targeting cache based COTS multi-core systems. We will confirm via measurements the main theoretical benefits of Memory Centric Scheduling (e.g. task isolation). Furthermore, we will describe an effective schedulability analysis using concepts from distributed systems.","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574011","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: 14

Designing Mixed Criticality Applications on Modern Heterogeneous MPSoC Platforms 在现代异构MPSoC平台上设计混合临界应用

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-01 DOI: 10.4230/LIPIcs.ECRTS.2019.27

G. Gracioli, Rohan Tabish, R. Mancuso, Reza Mirosanlou, R. Pellizzoni, M. Caccamo

{"title":"Designing Mixed Criticality Applications on Modern Heterogeneous MPSoC Platforms","authors":"G. Gracioli, Rohan Tabish, R. Mancuso, Reza Mirosanlou, R. Pellizzoni, M. Caccamo","doi":"10.4230/LIPIcs.ECRTS.2019.27","DOIUrl":"https://doi.org/10.4230/LIPIcs.ECRTS.2019.27","url":null,"abstract":"Multiprocessor Systems-on-Chip (MPSoC) integrating hard processing cores with programmable logic (PL) are becoming increasingly common. While these platforms have been originally designed for high performance computing applications, their rich feature set can be exploited to efficiently implement mixed criticality domains serving both critical hard real-time tasks, as well as soft real-time tasks. \u0000In this paper, we take a deep look at commercially available heterogeneous MPSoCs that incorporate PL and a multicore processor. We show how one can tailor these processors to support a mixed criticality system, where cores are strictly isolated to avoid contention on shared resources such as Last-Level Cache (LLC) and main memory. In order to avoid conflicts in last-level cache, we propose the use of cache coloring, implemented in the Jailhouse hypervisor. In addition, we employ ScratchPad Memory (SPM) inside the PL to support a multi-phase execution model for real-time tasks that avoids conflicts in shared memory. We provide a full-stack, working implementation on a latest-generation MPSoC platform, and show results based on both a set of data intensive tasks, as well as a case study based on an image processing benchmark application.","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124880835","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: 35

Scheduling Self-Suspending Tasks: New and Old Results 调度自暂停任务:新的和旧的结果

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-01 DOI: 10.4230/LIPIcs.ECRTS.2019.16

Jian-Jia Chen, T. Hahn, R. Hoeksma, Nicole Megow, G. V. D. Brüggen

引用次数: 8

DMAC: Deadline-Miss-Aware Control DMAC:错过截止日期控制

Euromicro Conference on Real-Time Systems Pub Date : 2019-07-01 DOI: 10.4230/LIPIcs.ECRTS.2019.1

P. Pazzaglia, C. Mandrioli, M. Maggio, A. Cervin

{"title":"DMAC: Deadline-Miss-Aware Control","authors":"P. Pazzaglia, C. Mandrioli, M. Maggio, A. Cervin","doi":"10.4230/LIPIcs.ECRTS.2019.1","DOIUrl":"https://doi.org/10.4230/LIPIcs.ECRTS.2019.1","url":null,"abstract":"The real-time implementation of periodic controllers requires solving a co-design problem, in which the choice of the controller sampling period is a crucial element. Classic design techniques limit the period exploration to safe values, that guarantee the correct execution of the controller alongside the remaining real-time load, i.e., ensuring that the controller worst-case response time does not exceed its deadline. This paper presents DMAC: the first formally-grounded controller design strategy that explores shorter periods, thus explicitly taking into account the possibility of missing deadlines. The design leverages information about the probability that specific sub-sequences of deadline misses are experienced. The result is a fixed controller, that on average works as the ideal clairvoyant time-varying controller that possesses knowledge of deadline hits and misses. We obtain a safe estimate of the hit and miss events using the scenario theory, that allows us to provide probabilistic guarantees. The paper analyzes controllers implemented using the Logical Execution Time paradigm and three different strategies to handle deadline miss events: killing the job, letting the job continue but skipping the next activation, and letting the job continue using a limited queue of jobs. Our experimental results show that our design proposal – i.e., that exploring the space where deadline can be missed and handled with different strategies – greatly outperforms classical control design techniques.","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125185753","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: 27

Worst-case Stall Analysis for Multicore Architectures with Two Memory Controllers 具有两个内存控制器的多核架构的最坏失速分析

Euromicro Conference on Real-Time Systems Pub Date : 2018-07-03 DOI: 10.4230/LIPIcs.ECRTS.2018.2

Muhammad Ali Awan, P. Souto, K. Bletsas, B. Akesson, E. Tovar

{"title":"Worst-case Stall Analysis for Multicore Architectures with Two Memory Controllers","authors":"Muhammad Ali Awan, P. Souto, K. Bletsas, B. Akesson, E. Tovar","doi":"10.4230/LIPIcs.ECRTS.2018.2","DOIUrl":"https://doi.org/10.4230/LIPIcs.ECRTS.2018.2","url":null,"abstract":"In multicore architectures, there is potential for contention between cores when accessing shared resources, such as system memory. Such contention scenarios are challenging to accurately analyse, from a worst-case timing perspective. One way of making memory contention in multicores more amenable to timing analysis is the use of memory regulation mechanisms. It restricts the number of accesses performed by any given core over time by using periodically replenished per-core budgets. Typically, this assumes that all cores access memory via a single shared memory controller. However, ever-increasing bandwidth requirements have brought about architectures with multiple memory controllers. These control accesses to different memory regions and are potentially shared among all cores. While this presents an opportunity to satisfy bandwidth requirements, existing analysis designed for a single memory controller are no longer safe. \u0000This work formulates a worst-case memory stall analysis for a memory-regulated multicore with two memory controllers. This stall analysis can be integrated into the schedulability analysis of systems under fixed-priority partitioned scheduling. Five heuristics for assigning tasks and memory budgets to cores in a stall-cognisant manner are also proposed. We experimentally quantify the cost in terms of extra stall for letting all cores benefit from the memory space offered by both controllers, and also evaluate the five heuristics for different system characteristics.","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129094945","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: 4

A Response-Time Analysis for Non-Preemptive Job Sets under Global Scheduling 全局调度下非抢占作业集的响应时间分析

Euromicro Conference on Real-Time Systems Pub Date : 2018-07-03 DOI: 10.4230/LIPIcs.ECRTS.2018.9

M. Nasri, Geoffrey Nelissen, Björn B. Brandenburg

{"title":"A Response-Time Analysis for Non-Preemptive Job Sets under Global Scheduling","authors":"M. Nasri, Geoffrey Nelissen, Björn B. Brandenburg","doi":"10.4230/LIPIcs.ECRTS.2018.9","DOIUrl":"https://doi.org/10.4230/LIPIcs.ECRTS.2018.9","url":null,"abstract":"An effective way to increase the timing predictability of multicore platforms is to use non-preemptive scheduling. It reduces preemption and job migration overheads, avoids intra-core cache interference, and improves the accuracy of worst-case execution time (WCET) estimates. However, existing schedulability tests for global non-preemptive multiprocessor scheduling are pessimistic, especially when applied to periodic workloads. This paper reduces this pessimism by introducing a new type of sufficient schedulability analysis that is based on an exploration of the space of possible schedules using concise abstractions and state-pruning techniques. Specifically, we analyze the schedulability of non-preemptive job sets (with bounded release jitter and execution time variation) scheduled by a global job-level fixed-priority (JLFP) scheduling algorithm upon an identical multicore platform. The analysis yields a lower bound on the best-case response-time (BCRT) and an upper bound on the worst-case response time (WCRT) of the jobs. In an empirical evaluation with randomly generated workloads, we show that the method scales to 30 tasks, a hundred thousand jobs (per hyperperiod), and up to 9 cores.","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121450279","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: 24

On Strong and Weak Sustainability, with an Application to Self-Suspending Real-Time Tasks 强可持续性和弱可持续性，以及自挂起实时任务的应用

Euromicro Conference on Real-Time Systems Pub Date : 2018-07-03 DOI: 10.4230/LIPIcs.ECRTS.2018.26

Felipe Cerqueira, Geoffrey Nelissen, Björn B. Brandenburg

{"title":"On Strong and Weak Sustainability, with an Application to Self-Suspending Real-Time Tasks","authors":"Felipe Cerqueira, Geoffrey Nelissen, Björn B. Brandenburg","doi":"10.4230/LIPIcs.ECRTS.2018.26","DOIUrl":"https://doi.org/10.4230/LIPIcs.ECRTS.2018.26","url":null,"abstract":"Motivated by an apparent contradiction regarding whether certain scheduling policies are sustainable, we revisit the topic of sustainability in real-time scheduling and argue that the existing definitions of sustainability should be further clarified and generalized. After proposing a formal, generic sustainability theory, we relax the existing notion of (strongly) sustainable scheduling policy to provide a new classification called weak sustainability. Proving weak sustainability properties allows reducing the number of variables that must be considered in the search of a worst-case schedule, and hence enables more efficient schedulability analyses and testing regimes even for policies that are not (strongly) sustainable. As a proof of concept, and to better understand a model for which many mistakes were found in the literature, we study weak sustainability in the context of dynamic self-suspending tasks, where we formalize a generic suspension model using the Coq proof assistant and provide a machine-checked proof that any JLFP scheduling policy is weakly sustainable with respect to job costs and variable suspension times. 2012 ACM Subject Classification Software and its engineering → Real-time schedulability","PeriodicalId":191379,"journal":{"name":"Euromicro Conference on Real-Time Systems","volume":"164 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127439844","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: 11

Verifying Weakly-Hard Real-Time Properties of Traffic Streams in Switched Networks 交换网络中流量流的弱硬实时性验证

Euromicro Conference on Real-Time Systems Pub Date : 2018-07-03 DOI: 10.4230/LIPIcs.ECRTS.2018.15

Leonie Ahrendts, Sophie Quinton, Thomas Boroske, R. Ernst

引用次数: 22