检索结果-内蒙古大学图书馆

priority inversion in DRTDBS: Challenges and Resolutions 18

Priority Inversion in DRTDBS: Challenges and Resolutions

5th ACM India Joint International Conference on Data Science and Management of Data (CoDS) / International Conference on Management of Data (COMAD)

作者： Pandey, Sarvesh Shanker, Udai Madan Mohan Malaviya Univ Technol Dept Comp Sci & Engn Gorakhpur 273010 Uttar Pradesh India

ISBN: (纸本)9781450363419

The primary(1) performance objective in distributed real-time database systems (DRTDBS) is to minimize the number of transactions missing their deadlines. Demanding nature of this objective makes traditional approaches and even existing approaches inadequate. The past researches have been mostly devoted to outspreading traditional transaction processing methods to resolve the issues. However, for the design of DRTDBS, new policies/protocols must be designed to resourcefully handle the concurrent execution of transactions. Our aim is to develop new concurrency control protocols, commit protocols and to compare their performance with existing protocols. Another plan is to extend our work to nested transaction model, replication environment and possibly mobile environment.

关键词： Concurrency Control Commit Protocol Data Conflict priority inversion priority Inheritance Distributed Real-time Database System

来源：评论

学校读者我要写书评

暂无评论

Solving the group priority inversion problem in a timed asynchronous system

引用

IEEE TRANSACTIONS ON COMPUTERS 2002年第8期51卷 900-915页

作者： Wang, Y Anceaume, E Brasileiro, F Greve, F Hurfin, M Southeast Univ Nanjung Peoples R China IRISA Rennes France Univ Fed Paraiba Dept Sistemas & Comp BR-58109970 Campina Grande Paraiba Brazil

We consider the priority inversion problem in an actively replicated system, priority inversion was originally defined in the context of nonreplicated systems. Therefore, we first introduce the concept of group priority inversion, which extends the concept of (local) priority inversion to the context of a group of processors that perform an actively replicated processing. We then present the properties of a request scheduling protocol to enforce a total ordering for the processing of requests while avoiding group priority inversions, These properties have been implemented in a protocol that relies on a timed asynchronous system model equipped with a failure detector of the class,S. The proposed solution allows us to replicate a critical server while ensuring that the processing of all the incoming requests is consistent (mechanisms for solving the atomic broadcast problem) and predictable (mechanisms for solving the group priority inversion problem), Thus, the described request scheduling protocol is a key component which can be used to develop fault-tolerant real-time applications in a timed asynchronous system.

关键词： priority inversion replicated servers timed asynchronous model agreement

来源：评论

学校读者我要写书评

暂无评论

Several methods of design and implementation to solve priority inversion problem in μC/OS-II

Several methods of design and implementation to solve priori...

引用

6th International Conference on Intelligent Networks and Intelligent Systems (ICINIS)

作者： Wang Xibo Jin Shan Yang Zhongling Shenyang Univ Technol Sch Informat Sci & Engn Shenyang 110178 Peoples R China Shenyang Metro Co Ltd Mech & Elect Equipment Ctr Dept Commun & Signal Shenyang 110178 Peoples R China

ISBN: (纸本)9781479928088

Multi-task concurrent execution and resource sharing based on preemptive scheduling strategy may cause priority inversion phenomenon in real-time systems. priority inversion phenomenon is the significant reason of unpredictable errors in real-time system;serious continuous priority inversion phenomenon will lead to real-time system collapse. The paper analyzes the phenomenon and the cause of the phenomenon, puts forward several design and implementation methods to solve priority inversion problem suitable for various application scenarios in mu C/OS-II. A priority exchange method is proposed to improve priority inheritance protocol. The proposed method limit priority inversion phenomenon to one level. Theoretical analyses and experimental results indicate that the methods to solve the priority inversion problem in mu C/OS-II are concise and effective, provides reasonable technical means for the safe running of complex real-time applications in mu C/OS-II.

关键词： real-time system priority inversion priority inheritance priority ceiling priority exchange

来源：评论

学校读者我要写书评

暂无评论

Transaction scheduling protocols for controlling priority inversion: A review

引用

COMPUTER SCIENCE REVIEW 2020年 35卷

作者： Pandey, Sarvesh Shanker, Udai MMM Univ Technol Dept CSE Gorakhpur 273010 Uttar Pradesh India

In advanced real-time distributed computing databases, the main performance criterion is to reduce the 'deadline miss' by the transactions;of course, consistency constraints also need to be satisfied. The goal of these applications is not to provide simply real-time transaction execution, but rather to provide a highly predictable, analysable, schedulable and reliable distributed computing platform to the users. The problem of resource conflicts amongst distributed real-time transactions and their handlings through various priority scheduling protocols highly affect the performance of the underlying applications. The past research works were mostly restricted to extend the traditional transaction processing techniques to resolve the issue of conflicts, and thus to improve the performance. The last review paper, largely on this issue, appeared in Shanker et al. (2008) [1];since then many noteworthy algorithms have been described in the literature. Till date, no study was found discussing transaction processing techniques with data conflict issue in focus. Hence, our objective is to comprehensively discuss the state-of-the-art transaction scheduling protocols with an emphasis on the handling of execute-execute & execute-commit conflicts, and real-time optimistic concurrency control (OCC) protocols. The strengths and weaknesses of existing approaches are also discussed. (C) 2019 Elsevier Inc. All rights reserved.

关键词： Commit protocol Concurrency control Execute-execute conflicts Execute commit conflicts priority inversion DRTDBS

来源：评论

学校读者我要写书评

暂无评论

Analysis and Modeling of a priority inversion Scheme for Starvation Free Controller Area Networks

引用

IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2010年第6期E93D卷 1504-1511页

作者： Lin, Cheng-Min Nan Kai Univ Technol Dept Comp & Commun Engn Tsao Tun 542 Nan Tou County Taiwan Nan Kai Univ Technol Grad Inst Elect Engn & Comp Sci Tsao Tun 542 Nan Tou County Taiwan

Control Area Network (CAN) development began in 1983 and continues today. The forecast for annual world production in 2008 is approximately 65-67 million vehicles with 10-15 CAN nodes per vehicle on average [1]. Although the CAN network is successful in automobile and industry control because the network provides low cost, high reliability, and priority messages, a starvation problem exists in the network because the network is designed to use a fixed priority mechanism. This paper presents a priority inversion scheme, belonging to a dynamic priority mechanism to prevent the starvation problem. The proposed scheme uses one bit to separate all messages into two categories with/without inverted priority. An analysis model is also constructed in this paper. From the model, a message with inverted priority has a higher priority to be processed than messages without inverted priority so its mean waiting time is shorter than the others. Two cases with and without inversion are implemented in our experiments using a probabilistic model checking tool based on an automatic formal verification technique. Numerical results demonstrate that low-priority messages with priority inversion have better expression in the probability in a full queue state than others without inversion. However, our scheme is very simple and efficient and can be easily implemented at the chip level.

关键词： Distributed control priority queueing priority inversion controller area network embedded control

来源：评论

学校读者我要写书评

暂无评论

Integrated scheduling for reducing the delays by priority inversion in real-time web service

引用

IEICE TRANSACTIONS ON COMMUNICATIONS 2003年第7期E86B卷 2143-2153页

作者： Jung, SY Kang, BJ Choi, K Chung, KH Ajou Univ Dept IE&CE Suwon South Korea Ajou Univ Grad Sch I&C Suwon South Korea Ajou Univ Sch EE Suwon South Korea

This paper proposes a real-time scheduling mechanism for web server that finds a way to solve so-called priority inversion problem between tasks handling real-time web requests with higher priorities and tasks with lower priorities like HTML requests. The priority inversion problem of web server stems from operating two independent schedulers, web scheduler and kernel scheduler, without exchanging scheduling information or considering the requirement of each other. In the proposed mechanism, two schedulers are integrated in a kernel and the integrated scheduler schedules real-time web tasks and other application tasks together based on their priorities. Since the unified scheduler sees all tasks simultaneously in system, it can schedule the tasks with their absolute priorities and reduce the execution delay caused by the priority inversion. The proposed mechanism provides web server with a better chance to efficiently serve real-time web requests. The feasibility and performance of the proposed mechanism are empirically shown on an embedded system.

关键词： WWW Web service real-time priority inversion scheduling

来源：评论

学校读者我要写书评

暂无评论

RESEARCH OF priority inversion IN REAL-TIME SYSTEM

RESEARCH OF PRIORITY INVERSION IN REAL-TIME SYSTEM

引用

2007中国宁波国际计算机科学与技术学术大会

作者： Zhao Qi Suo Xiaoran Department of Electronic Engineering Wuxi Institute of Commerce School of Info & Electric Technology Hebei University of Engineering

A real-time multitasking operating system requires rapid response to external *** it is very important to select an appropriate task scheduling *** multiple tasks seeking access to shared resources will lead to priority *** kinds of solutions to resolve the problem are proposed,and their disadvantages are *** technique of priority inheritance is analyzed in detail,and is improved *** and tests have proved the efficiency and practicability of this way to resolve priority inversion.

关键词： Real-time system Scheduling algorithm Semaphore priority inversion priority inheritance

来源：评论

学校读者我要写书评

暂无评论

Reservation based protocol for resolving priority inversions in composable conveyor systems

引用

JOURNAL OF SYSTEMS ARCHITECTURE 2017年 74卷 14-29页

作者： Mahamadi, Abdelrhman Chippa, Mukesh Sastry, Shivakumar Univ Akron ECE Dept Complex Engn Syst Lab Akron OH 44325 USA

We present a reservation based protocol for resolving priority inversions in Composable Conveyor Systems. These systems represent a class of networked multi-processor systems that are used to physically transport entities from inputs to outputs. The absence of shared memory and the interaction between the cyber and physical subsystems present many challenges such as priority inversion. We view the end-to end transport of an entity as a task and discuss how these systems admit a rich set of task models. Like in other real-time systems, a priority inversion is said to occur when a high-priority task is blocked by a lower-priority task for an unbounded duration of time. We present an approach to compute the average waiting time for entities, establish properties of the proposed protocol and present simulation results that demonstrate the efficacy of the proposed protocol. In the future, this protocol can be extended to other task models and a larger class of decentralized systems for advanced manufacturing. (C) 2016 Elsevier B.V. All rights reserved.

关键词： priority inversion Networked embedded systems Advanced manufacturing

来源：评论

学校读者我要写书评

暂无评论

Resolving priority inversions in composable conveyor systems

引用

JOURNAL OF SYSTEMS ARCHITECTURE 2014年第6期60卷 509-518页

作者： Sastry, Shivakumar Gokhale, Aniruddha Univ Akron Dept Elect & Comp Engn Akron OH 44325 USA Vanderbilt Univ Dept Elect Engn & Comp Sci Nashville TN 37325 USA

The well known problem of priority inversions that occurs in classical real-time systems also manifests in decentralized cyber-physical systems. Using a specific example of composable conveyor systems, we show how priority inversions hinder the transport of entities through the conveyor systems. We present a novel adaptation of the classical priority inheritance protocol for resolving these cyber-physical priority inversions. While the approach resolves cyber-physical priority inversions, the structure and constraints of the conveyor systems cause the jitter associated with the end-to-end latency of the highest priority parts to increase. Further, these constraints also limit the applicability of the classical priority ceiling protocol in this class of cyber-physical systems. Simulation results demonstrate the correctness and reasonable communication overhead of the approach. (C) 2014 Elsevier B.V. All rights reserved.

关键词： Real-time systems priority inversion Composable conveyors Networked systems

来源：评论

学校读者我要写书评

暂无评论

Achieving Consistent Real-Time Latency at Scale in a Commodity Virtual Machine Environment Through Socket Outsourcing-Based Network Stacks

引用

IEEE ACCESS 2018年 6卷 69961-69977页

作者： Garcia, Oscar F. Shinjo, Yasushi Pu, Calton Univ Tsukuba Dept Comp Sci Tsukuba Ibaraki 3058573 Japan Georgia Inst Technol Coll Comp Atlanta GA 30332 USA Georgia Inst Technol Coll Comp Software Atlanta GA 30332 USA

It is challenging to achieve a consistent real-time (RT) response time in commodity virtual machine (VM) environments because they have longer and more complex network protocol stacks. This paper analyzes such network stacks and proposes a method that achieves consistent latency in a Linux KVM-based hosted environment. The analysis identifies a priority inversion in the interrupt-first host kernel of vanilla Linux, and the proposed method addresses it by using the PREEMPT_RT patch. Subsequently, the analysis identifies another priority inversion in softirq handling of the host kernel. The proposed method addresses it by dividing softirq handling into RT and non-RT types. The analysis then identifies the cache pollution problem by co-located non-RT servers and the latter priority inversion in a guest kernel. The proposed method addresses them by socket outsourcing, in which a guest kernel delegates network processing to the host kernel. The proposed method achieved consistent latency. Compared to the threaded interrupt handling method, the proposed method reduced the standard deviation (SD) of the latencies of a simple RT server by a factor of 6, achieving 5.6% higher throughput and 32% lower CPU utilization. Compared to the exclusive CPU method, the proposed method reduced the SD by a factor of 2 and prevented underutilization of the exclusive CPU. The proposed method was more scalable in terms of the number of RT VMs. A four-CPU host was able to execute 40 RT VMs using the proposed method while maintaining the throughputs of non-RT servers.

关键词： KVM Linux priority inversion real-time latency socket outsourcing

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：