Deadlock Detection:Background,Techniques,and Future Improvements

Deadlock detection is an essential aspect of concurrency control in parallel and distributed systems,as it ensures the efficient utilization of resources and prevents indefinite delays.This paper presents a comprehensive analysis of the various deadlock detection techniques,including static and dynamic approaches.We discuss the future improvements associated with deadlock detection and provide a comparative evaluation of these techniques in terms of their accuracy,complexity,and scalability.Furthermore,we outline potential future research directions to improve deadlock detection mechanisms and enhance system performance.

Type-2 Neutrosophic Set and Their Applications in Medical Databases Deadlock Resolution

Electronic patient data gives many advantages,but also new difficulties.Deadlocks may delay procedures like acquiring patient information.Distributed deadlock resolution solutions introduce uncertainty due to inaccurate transaction properties.Soft computing-based solutions have been developed to solve this challenge.In a single framework,ambiguous,vague,incomplete,and inconsistent transaction attribute information has received minimal attention.The work presented in this paper employed type-2 neutrosophic logic,an extension of type-1 neutrosophic logic,to handle uncertainty in real-time deadlock-resolving systems.The proposed method is structured to reflect multiple types of knowledge and relations among transactions’features that include validation factor degree,slackness degree,degree of deadline-missed transaction based on the degree of membership of truthiness,degree ofmembership of indeterminacy,and degree ofmembership of falsity.Here,the footprint of uncertainty(FOU)for truth,indeterminacy,and falsity represents the level of uncertainty that exists in the value of a grade of membership.We employed a distributed real-time transaction processing simulator(DRTTPS)to conduct the simulations and conducted experiments using the benchmark Pima Indians diabetes dataset(PIDD).As the results showed,there is an increase in detection rate and a large drop in rollback rate when this new strategy is used.The performance of Type-2 neutrosophicbased resolution is better than the Type-1 neutrosophic-based approach on the execution ratio scale.The improvement rate has reached 10%to 20%,depending on the number of arrived transactions.

Optimal deadlock avoidance Petri net supervisors for automated manufacturing systems

Deadlock avoidance problems are investigated for automated manufacturing systems with flexible routings. Based on the Petri net models of the systems, this paper proposes, for the first time, the concept of perfect maximal resourcetransition circuits and their saturated states. The concept facilitates the development of system liveness characterization and deadlock avoidance Petri net supervisors. Deadlock is characterized as some perfect maximal resource-transition circuits reaching their saturated states. For a large class of manufacturing systems, which do not contain center resources, the optimal deadlock avoidance Petri net supervisors are presented. For a general manufacturing system, a method is proposed for reducing the system Petri net model so that the reduced model does not contain center resources and, hence, has optimal deadlock avoidance Petri net supervisor. The controlled reduced Petri net model can then be used as the liveness supervisor of the system.

Robust Deadlock Avoidance Policy for Automated Manufacturing System With Multiple Unreliable Resources

This work studies the robust deadlock control of automated manufacturing systems with multiple unreliable resources. Our goal is to ensure the continuous production of the jobs that only require reliable resources. To reach this goal, we propose a new modified Banker's algorithm(MBA) to ensure that all resources required by these jobs can be freed. Moreover,a Petri net based deadlock avoidance policy(DAP) is introduced to ensure that all jobs remaining in the system after executing the new MBA can complete their processing smoothly when their required unreliable resources are operational. The new MBA together with the DAP forms a new DAP that is robust to the failures of unreliable resources. Owing to the high permissiveness of the new MBA and the optimality of the DAP, it is tested to be more permissive than state-of-the-art control policies.

Deadlock-free Supervisor Design for Robotic Manufacturing Cells With Uncontrollable and Unobservable Events

In this paper,a deadlock prevention policy for robotic manufacturing cells with uncontrollable and unobservable events is proposed based on a Petri net formalism.First,a Petri net for the deadlock control of such systems is defined.Its admissible markings and first-met inadmissible markings(FIMs)are introduced.Next,place invariants are designed via an integer linear program(ILP)to survive all admissible markings and prohibit all FIMs,keeping the underlying system from reaching deadlocks,livelocks,bad markings,and the markings that may evolve into them by firing uncontrollable transitions.ILP also ensures that the obtained deadlock-free supervisor does not observe any unobservable transition.In addition,the supervisor is guaranteed to be admissible and structurally minimal in terms of both control places and added arcs.The condition under which the supervisor is maximally permissive in behavior is given.Finally,experimental results with the proposed method and existing ones are given to show its effectiveness.

A Deadlock-Avoidance Dispatching Method for Multiple-Load AGVs Based Transportation System

In recent years,multiple-load automatic guided vehicle(AGV)is increasingly used in the logistics transportation fields,owing to the advantages of smaller fleet size and fewer occurrences of traffic congestion.However,one main challenge lies in the deadlock-avoidance for the dispatching process of a multiple-load AGV system.To prevent the system from falling into a deadlock,a strategy of keeping the number of jobs in the system(NJIS)at a low level is adopted in most existing literatures.It is noteworthy that a low-level NJIS will make the processing machine easier to be starved,thereby reducing the system efficiency unavoidably.The motivation of the paper is to develop a deadlock-avoidance dispatching method for a multiple-load AGV system operating at a high NJIS level.Firstly,the deadlock-avoidance dispatching method is devised by incorporating a deadlock-avoidance strategy into a dispatching procedure that contains four sub-problems.In this strategy,critical tasks are recognized according to the status of workstation buffers,and then temporarily forbidden to avoid potential deadlocks.Secondly,three multiattribute dispatching rules are designed for system efficiency,where both the traveling distance and the buffer status are taken into account.Finally,a simulation system is developed to evaluate the performance of the proposed deadlock-avoidance strategy and dispatching rules at different NJIS levels.The experimental results demonstrate that our deadlock-avoidance dispatching method can improve the system efficiency at a high NJIS level and the adaptability to various system settings,while still avoiding potential deadlocks.

Deadlock-free dynamic resource assignment in multi-robot systems with multiple missions:application in wireless sensor networks

In unstructured environments, dynamic resource assignment is required for effective cooperation of robot teams. In some scenarios, robots are in charge of executing multiple missions simultaneously. This creates risks of deadlock due to the presence of shared resources among various missions. The main contribution of this paper is the development of a novel approach that combines the one-step look-ahead deadlock avoidance policy with dynamic resource assignment. The dynamicresource assignment is achieved using greedy resource assignment for multi-mission robot teams in the framework of a matrix-based discrete event controller. Simulation results are presented in MATLAB to discuss in detail the proposed control strategy. The paper also discusses the toolkit developed in LabVIEW which is used to implement this control framework using a suitable example.

Deadlock prevention for flexible manufacturing system

Deadlock must be prevented via the shop controller during the flexible manufacturing system （FMS） performing. Various models have been tried for the analysis and design of shop controller. Petri net is suitable to describe the dynamic behavior of the discrete event system, such as concurrency, conflict and deadlock, however, the verification of the .system behavior needs structure analysis with complex theoretical proof method. Temporal logic model checking has important advantages over traditional theorem prover. It is flatly automatic and can produce possible counter-example which is particularly important in finding subtle error in complex transition systems. In this paper, a new method for the deadlock prevention based on Petri net and Temporal Logic model checking is presented. The specification in the Temporal Logic is expressed according to some result of structure analysis of the Petri net. The model checking is employed to execute the formal verification, which will conduct an exhaustive exploration of all possible behaviors. Finally, an example is presented to demonstrate how the method works.

DEADLOCK-FREE SCHEDULING METHOD BASED ON PETRI NET AND GA

An efficient algorithm for finding an optimal deadlock-free schedule in amanufacturing system with very limited buffer is presented. This algorithm is based on the effectivegenetic algorithm (GA) search method, and a formal Petri net structure is introduced to detect thetoken player assuring deadlock-free. In order to make the scheduling strategy generated by GA meetthe required constraint of deadlock-free, Petri net is involved to make the implementation of thejob scheduling in an FMS deadlock-free. The effectiveness and efficiency of the proposed approach isillustrated by using an example.

DPTSV:A Dynamic Priority Task Scheduling Strategy for TSS Deadlock Based on Value Evaluation

This paper analyzes the threat of TCG Software Stack(TSS)/TCM Service Module(TSM) deadlock in multi-user environment such as cloud and discusses its causes and mechanism.In addition,this paper puts forward a dynamic priority task scheduling strategy based on value evaluation to handle this threat.The strategy is based on the implementation features of trusted hardware and establishes a multi-level ready queue.In this strategy,an algorithm for real-time value computing is also designed,and it can adjust the production curves of the real time value by setting parameters in different environment,thus enhancing its adaptability,which is followed by scheduling and algorithm description.This paper also implements the algorithm and carries out its performance optimization.Due to the experiment result from Intel NUC,it is shown that TSS based on advanced DPTSV is able to solve the problem of deadlock with no negative influence on performance and security in multi-user environment.

A Graph Theoretic Method to Handle Deadlocks in Flexible Manufacturing Cells

The deadlock-handling scheme is based on a bipartite graph model of the part-machine relationship in the manufac- turing cell.A distinction is made between permanent deadlock and transient deadlock.Permanent deadlock depicts a manufactur- ing system state where parts are irrevocably blocked and where external intervention is required to resolve the deadlock,whereas a transient deadlock indicates that there is a positive probability that the deadlock will resolve itself over time.To recover from dead- locks,one control policy is studied:resolve deadlocks in the manufacturing cell.Under the policy,it is shown that it is sufficient to resolve any cycle in the set of deadlocked parts to resolve the deadlock.Finally,we estimate the deadlocks in flexible manufactur- ing cells.

USING COLORED-TIMED PETRI NET FOR THE SOLUTION OF DEADLOCK IN A FLEXIBLE ASSEMBLY SYSTEM

A colored timed Petri net(CTPN)modeling technique is developed for flexible assembly system(FAS) In particular,one section is devoted to the deadlock nodel based on the Petri net The rule of the deadlock error recovery is given Through the analysis of the behavioral properties of the FAS with the deadlock recovery model,the deadlock problem would be solved in the system.

Kind of deadlock-free scheduling method

Deadlock must be avoided in a manufacturing system. In this paper, an efficient algorithm for finding an optimal deadlock-free schedules in a manufacturing system with very limited buffer is presented. This algorithm is based on the effective genetic algorithm (GA) search method, and a formal Petri net structure is introduced to detect the token player assuring deadlock-free. In order to make the scheduling strategy generated by GA meet the required constraint of deadlock-free, some results of the structure analysis of Petri net are involved as a criterion to select deadlock-free schedule from the population generated by GA. The effectiveness and efficiency of the proposed approach is illustrated by using an example.

Deadlock detection using abstraction refinement

This paper adopts counterexample guided abstraction refinement scheme to alleviate the state explosion problem of deadlock detection. We extend the classical labeled transition system models by qualifying transitions as certain and uncertain to make deadlock-freedom conservative, i.e. if the abstraction of a system is deadlock-free, then the system is deadlock-free. An abstraction refinement approach to deadlock detection is proposed, and the correctness of the approach is proved.

A distributed deadlock detection algorithm for mobile computing system

The mode of mobile computing originated from distributed computing and it has the un-idempotent operation property, therefore the deadlock detection algorithm designed for mobile computing systems will face challenges with regard to correctness and high efficiency. This paper attempts a fundamental study of deadlock detection for the AND model of mobile computing systems. First, the existing deadlock detection algorithms for distributed systems are classified into the resource node dependent (RD) and the resource node independent (RI) categories, and their corresponding weaknesses are discussed. Afterwards a new RI algorithm based on the AND model of mobile computing system is presented. The novelties of our algorithm are that: 1) the blocked nodes inform their predecessors and successors simultaneously; 2) the detection messages (agents) hold the predecessors information of their originator; 3) no agent is stored midway. Additionally, the quit-inform scheme is introduced to treat the excessive victim quitting problem raised by the overlapped cycles. By these methods the proposed algorithm can detect a cycle of size n within n-2 steps and with (n^2-n-2)/2 agents. The performance of our algorithm is compared with the most competitive RD and RI algorithms for distributed systems on a mobile agent simulation platform. Experiment results point out that our algorithm outperforms the two algorithms under the vast majority of resource configurations and concurrent workloads. The correctness of the proposed algorithm is formally proven by the invariant verification technique.

The Implementation of a Communication Deadlock Analysis Based on the Theory of Deadlock Analysis for the Actor Model

We present a unique approach for communication deadlock analysis for actor-model which has an under-approximated analysis result. Our analysis detects narrowly defined communication deadlocks by finding a cyclic dependency relation in a novel dependency graph called the slave dependency graph. The slave dependency graph is based on a new relationship between Actors, slave dependency, defined by us. After that, we implement this theory in Soot, an analysis tool for Java, and use it to analyze actor-based Java program realized by Akka, a Java library that allows actor-based programming. We argue that our analysis can detect a specific kind of communication deadlock with the precise result, but has many limitations.

Elementary Siphons of Petri Nets and Deadlock Control in FMS

For responsiveness, in the Petri nets theory framework deadlock prevention policies based elementary siphons control are often utilized to deal with deadlocks caused by the sharing of resources in flexible manufacturing system (FMS) which is developing the theory of efficient strict minimal siphons of an S3PR. Analyzer of Petri net models and their P-invariant analysis, and deadlock control are presented as tools for modelling, efficiency structure analysis, control, and investigation of the FMSs when different policies can be implemented for the deadlock prevention. We are to show an effective deadlock prevention policy of a special class of Petri nets namely elementary siphons. As well, both structural analysis and reachability graph analysis and simulation are used for analysis and control of Petri nets. This work is successfully applied Petri nets to deadlock analysis using the concept of elementary siphons, for design of supervisors of some supervisory control problems of FMS and simulation of Petri net tool with MATLAB.

Application of modified banker’s algorithm in FMS deadlock problem

Presents a method for deadlock avoidance algorithm used in Flexible Manufacturing System(FMS). This method is an improvement of the Banker algorithm. The Banker algorithm is commonly used in the Operating System (OS), but some improvements will have to be made on the algorithm if this algorithm is used in FMS. The difference between the process in operating system and the job in the FMS is fully discussed. Based on this difference, the improvement is made. In order to improve the algorithm, formal methods are adopted to the manufacturing systems. The simulation model is translated into a format suitable for model checking. That is, the model is written into PROMELA, the input language of the popular model checker SPIN. After that, SPIN is used to verify that the model does not have deadlock. This algorithm proves to be highly effective in practice.

Research on efficient edge-chasing deadlock detection/resolution for distributed systems

Numerous edge-chasing deadlock detection algonthms were developed lor the cycle detection in distributed systems, but their detections had the n steps speed limitation and n （ n- 1） overhead limitation to detect a cycle of size n under the one-resource request model. Since fast deadlock detection is critical, this paper proposed a new algorithm to speed up the detection process. In our algorithm, when the running of a transaction node is blocked, the being requested resource nodes reply it with the waiting or being waited message simultaneously, so the blocked node knows both its predecessors and successors, which helps it detecting a cycle of size 2 directly and locally. For the cycle of size n （ n 〉 2）, a special probe is produced which has the predecessors information of its originator, so the being detected nodes know their indirect predecessors and direct successors, and can detect the cycle within n - 2 steps. The proposed algorithm is formally proved to be correct by the invariant verification method. Performance evaluation shows that the message overhead of our detection is （ n^2 - n - 2）/2, hence both the detection speed and message cost of the proposed algorithm are better than that of the existing al gorithms.

Deadlock Detection and Avoidance in Static Step Topology under Distributed Environment

During the past years, the distributed computing approach has become very popular due to various advantages over centralized approach. In the distributed approach, the execution of a process has reduced and also it requires low cost for installation. Many of the researchers are using the modeling approach for solution of the software and hardware architecture research problems. The most popular approach of modeling is known as Unified Modeling Language based on the object-oriented technology. In the present work, a method of deadlock detection is explained for the newly proposed static step topology for the distributed network. In the step topology, the processes are taken as a task, sub task, macro, subroutine, etc which are executed in reflexive and symmetric manners when the systems are interconnected to each other under distributed environment and avoidance technique is also presented for the same. The deadlock detection technique is presented through a UML class model.