Proceedings 16th IEEE Real-Time Systems Symposium最新文献_第2页

MiThOS-a real-time micro-kernel threads operating system 一个实时的微内核线程操作系统

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495195

F. Mueller, V. Rustagi, T. Baker

{"title":"MiThOS-a real-time micro-kernel threads operating system","authors":"F. Mueller, V. Rustagi, T. Baker","doi":"10.1109/REAL.1995.495195","DOIUrl":"https://doi.org/10.1109/REAL.1995.495195","url":null,"abstract":"MiThOS (Micro-kernel Threads Operating System) is an experimental operating system for embedded systems. The system kernel is a first implementation of the POSIX Minimal Real-Time System Profile. It is based on prior work of a library implementation of Pthreads (POSIX threads). The system is fully preemptive. It supports multi-threading within a single process environment with shared kernel and user space, i.e. real-time tasks are mapped onto POSIX threads. It exhibits remarkable timing predictability intended for hard real-time requirements. This is achieved by a careful design of only few device drivers. The system has been implemented and tested on the SPARC VME architecture. The system includes a fast context switching algorithm for the SPARC which outperforms the context switch under SunOS and matches the performance under Solaris. It supports selective enabling and disabling of hardware components (MMU, caches, etc.) since its sources are available. Furthermore, an implementation-defined extension of POSIX threads for deadline scheduling is presented. Overall, the system exhibits slightly faster performance than SunOS 4.x and is considerably more predictable in its timing behavior. Applications of the kernel range from evaluating the overhead of new language features in Ada 95 and its runtime system, verifying static timing predictions on a bare machine, to providing the operating system for small embedded system that require a high timing predictability.","PeriodicalId":231426,"journal":{"name":"Proceedings 16th IEEE Real-Time Systems Symposium","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132104195","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: 6

A graphical language with formal semantics for the specification and analysis of real-time systems 一种具有形式化语义的图形语言，用于实时系统的规范和分析

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495217

H. Ben-Abdallah, Insup Lee, Jin-Young Choi

引用次数: 24

Distributed pinwheel scheduling with end-to-end timing constraints 具有端到端时序约束的分布式风车调度

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495207

Chih-wen Hsueh, Kwei-Jay Lin, Nong Fan

引用次数: 41

Some performance issues for transactions with firm deadlines 具有确定截止日期的事务的一些性能问题

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495221

Y. Tay

引用次数: 6

Compiling Modechart specifications 编译Modechart规范

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495215

C. Puchol, A. Mok, D. Stuart

引用次数: 12

Efficient microarchitecture modeling and path analysis for real-time software 实时软件的高效微体系结构建模和路径分析

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495219

Yau-Tsun Steven Li, S. Malik, A. Wolfe

{"title":"Efficient microarchitecture modeling and path analysis for real-time software","authors":"Yau-Tsun Steven Li, S. Malik, A. Wolfe","doi":"10.1109/REAL.1995.495219","DOIUrl":"https://doi.org/10.1109/REAL.1995.495219","url":null,"abstract":"Real-time systems are characterized by the presence of timing constraints in which a task must be completed within a specific amount of time. This paper examines the problem of determining the bound on the worst case execution time (WCET) of a given program on a given processor There are two important issues in solving this problem: (i) program path analysis, which determines what sequence of instructions will be executed in the worst case, and (ii) microarchitecture modeling, which models the hardware system and determines the WCET of a known sequence of instructions. To obtain a tight estimate on the bound both these issues must be addressed accurately and efficiently. The latter is becoming difficult to model for modern processors due to the presence of pipelined instruction execution units and cached memory systems. Because of the complexity of the problem, all existing methods that we know of focus only on one of above issues. This limits the accuracy of the estimated bound and the size of the program that can be analyzed. We present a more effective solution that addresses both issues and uses an integer linear programming formulation to solve the problem. This solution is implemented in the program cinderella which currently targets the Intel i960KB processor and we present some experimental results of using this tool.","PeriodicalId":231426,"journal":{"name":"Proceedings 16th IEEE Real-Time Systems Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129049306","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: 232

A software fault injection tool on real-time Mach 实时Mach的软件故障注入工具

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495203

S. Dawson, F. Jahanian, T. Mitton

引用次数: 10

Value vs. deadline scheduling in overload conditions 重载条件下的值与截止日期调度

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495199

G. Buttazzo, M. Spuri, F. Sensini

{"title":"Value vs. deadline scheduling in overload conditions","authors":"G. Buttazzo, M. Spuri, F. Sensini","doi":"10.1109/REAL.1995.495199","DOIUrl":"https://doi.org/10.1109/REAL.1995.495199","url":null,"abstract":"We present a comparative study among scheduling algorithms which use different priority assignments and different guarantee mechanisms to improve the performance of a real-time system during overload conditions. In order to enhance the quality of service, we assume that tasks are characterized not only by a deadline, but also by an importance value. The performance of the scheduling algorithm is then evaluated by computing the cumulative value gained on a task set, i.e. the sum of the values of those tasks that completed by their deadline. The purpose of this simulation study was twofold. Firstly, we wanted to discover which priority assignment is able to achieve the best performance in overload conditions. Secondly, we were interested in understanding how the pessimistic assumptions made in the guarantee test affect the performance of the scheduling algorithms, and how much a reclaiming mechanism can compensate this degradation. Simulation results show that, without any admission control, value-density scheduling performs best. Simple admission control based on worst case estimates of the load worsen the performance of all value based algorithms. EDF scheduling performs best if admission control is used along with a reclaiming mechanism that takes advantage of early completions. Finally, scheduling by deadline before overload and by value during overload works best in most practical conditions.","PeriodicalId":231426,"journal":{"name":"Proceedings 16th IEEE Real-Time Systems Symposium","volume":"163 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116882832","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: 166

A scalable real-time synchronization protocol for distributed systems 分布式系统的可扩展实时同步协议

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495192

I. Rhee, G. Martin

引用次数: 10

Real-time computing with lock-free shared objects 无锁共享对象的实时计算

Proceedings 16th IEEE Real-Time Systems Symposium Pub Date : 1995-12-05 DOI: 10.1109/REAL.1995.495193

James H. Anderson, Srikanth Ramamurthy, K. Jeffay

{"title":"Real-time computing with lock-free shared objects","authors":"James H. Anderson, Srikanth Ramamurthy, K. Jeffay","doi":"10.1109/REAL.1995.495193","DOIUrl":"https://doi.org/10.1109/REAL.1995.495193","url":null,"abstract":"This paper considers the use of lock-free shared objects within hard real-time systems. As the name suggests, lock-free shared objects are distinguished by the fact that they are not locked. As such, they do not give rise to priority inversions, a key advantage over conventional, lock-based object-sharing approaches. Despite this advantage, it is not immediately apparent that lock-free shared objects can be employed if tasks must adhere to strict timing constraints. In particular, lock-free object implementations permit concurrent operations to interfere with each other, and repeated interferences can cause a given operation to take an arbitrarily long time to complete. The main contribution of this paper is to show that such interferences can be bounded by judicious scheduling. This work pertains to periodic, hard real-time tasks that share lock-free objects on a uniprocessor. In the first part of the paper, scheduling conditions are derived for such tasks, for both static and dynamic priority schemes. Based on these conditions, it is formally shown that lock-free object-sharing approaches can be expected to incur much less overhead than approaches based on wait-free objects or lock-based schemes. In the last part of the paper, this conclusion is validated experimentally through work involving a real time desktop videoconferencing system.","PeriodicalId":231426,"journal":{"name":"Proceedings 16th IEEE Real-Time Systems Symposium","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124584833","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: 167