Results and Discussion
This section describes the results and implications related to the objectives of each study which are based on the results of the synthesis stage of the data. Here are presented the limitations of the study and recommendations. A new model introduced in the paper "Using Deep Learning for Deadlock Detection in Intelligent Software Systems" (ROMDHANI et al., 2025) is proposed in order to do real-time deadlock detection in intelligent software systems. This method is based on the combination of Petri Nets, modeling the interaction of the tasks with the resources, and the modelling of the dynamics of the systems, with the artificial neural networks, in order to classify the states of the systems and their deadlock situations with high rates of recovery of accuracy. The training is carried out with different synthetic system instances of normal behaviour and prone to deadlocks. The results show that the model hybrid Petri Net+ANN is being able to improve the classical machine learning solutions (decision trees, random forests, .up to here continue similar.) and pure neural solutions, reaching the values of 100% accuracy, precision and recall in the tests carried out.
"Addressing deadlock in large-scale, complex rail networks via multi-agent deep reinforcement learning" (Bretas et al., 2023) has emerged as a highly effective means of facilitating adaptive deadlock avoidance and resolution in large-scale distributed systems with inherent vigour and dynamism like networks of railways. Intelligent agents (trains) adopt traffic management policies through centralised learning with decentralised execution achieving considerable improvement over the traditional first-come-first-serve (FCFS) heuristic. The introduction of reward shaping and deadlock lists leads to a great reduction of the deadlock frequency and offers much greater robustness to the policy, especially in high density situations.
Demonstrating a fault-tolerant observer-based leader-following consensus strategy based on utilizing virtual actuators and LPV modeling, "Fault-tolerant observer-based leader-following consensus control for LPV multi-agent systems using virtual actuators" (Trejo et al., 2024) illustrates its effectiveness in a cyber-physical domain such as UAV team coordination where the maneuvering of unmanned aerial vehicles in set formations and specific control tasks remains intact even when several actuators (like rotors) cease to function. Actual quadcopter simulation results are used to corroborate this claim.
Regarding consortium blockchains, “The Evolution and Optimization Strategies of a PBFT Consensus Algorithm for Consortium Blockchains” (Yuan et al., 2025) discusses how PBFT (Practical Byzantine Fault Tolerance) consensus can be refined through an improvement in the structure through hierarchical node classification, administrative measures, and hybrid remuneration measures. Such improvements significantly increase throughput and robustness, but the implementation of such improvements requires a balance between communicative complexity and scalability.
Table 2.
Characteristics of the Selected Studies.
Table 2.
Characteristics of the Selected Studies.
| Id |
Year |
Purpose |
Summery of Findings |
| #1 |
2024 |
Analyze and prevent deadlocks in payment channel networks using resource allocation graphs. |
Identified and mitigated NP-complete deadlock risks, increasing scalability and reliability in blockchain transaction networks. |
| #2 |
2023 |
Enable efficient task scheduling in distributed systems by preventing deadlocks via task removal inference. |
Proposed an improved multi-task scheduling algorithm that ensures system convergence and resource utilization during task allocation. |
| #3 |
2022 |
Provide deadlock/livelock avoidance in manufacturing using Petri nets and critical distance method. |
Maximally permissive approach efficiently avoids deadlocks in complex manufacturing by reducing computational complexity. |
| #4 |
2022 |
Accelerate MPI deadlock detection through trace compression techniques. |
Trace compression reduced detection time, speeding fault identification in message-passing programs. |
| #5 |
2021 |
Detect and recover deadlocks in Flexible Manufacturing Systems via resource flow graphs. |
Resource flow graph approach enables fast, accurate recognition and recovery from deadlocks, ensuring smooth FMS operation. |
| #6 |
2021 |
Resolve collisions and deadlocks in multi-AGV transport by zone-decomposition and online control. |
Unidirectional zone decomposition improved collision/deadlock handling, outperforming former approaches in transport tests. |
| #7 |
2021 |
Offer adaptive deadlock control in Petri net systems with unreliable resources. |
Siphon control method enables robust operation even during frequent machine or resource failures. |
| #8 |
2022 |
Compare deadlock avoidance/prevention in autonomous vehicle resource provisioning over 6G. |
Smart cooperative edge control strategies outperformed traditional systems in real-vehicle network tests. |
| #9 |
2021 |
Introduce the Vagabond non-exhaustive algorithm for fast deadlock detection in distributed models. |
Distinctly detects and classifies deadlock vs. termination with little parameter tuning or reachability search. |
| #10 |
2021 |
Use graph theory and centrality to optimize resource allocation and avoid deadlocks in databases. |
Demonstrated how critical resource requests can be prioritized to maintain deadlock-free large data operations. |
| #11 |
2023 |
Predict and avoid deadlocks in fog computing with multi-module load balancing. |
Preemptive deadlock detection maintains load balance, ensuring real-time reliability and system uptime. |
| #12 |
2022 |
Guarantee deadlock-free routing by optimal hub placement in payment channel networks. |
Adaptive hub placement improves throughput and guarantees deadlock-free payments as network scales. |
| #13 |
2023 |
Speed up deadlock avoidance in flexible manufacturing with Petri net event circuit structures. |
Event circuit methods prevent deadlocks far more efficiently than prior state-intensive techniques. |
| #14 |
2022 |
Develop fault-tolerant, deadlock-free routing for chiplet (2.5D) network-on-chip systems. |
“DeFT” algorithm maintains routing and fault tolerance across vertical links, outperforming alternatives. |
| #15 |
2022 |
Deliver a dynamic tool for broad deadlock detection via generalized dependency. |
“UnHang” detects lock and condition-variable deadlocks, supporting more real-world concurrency scenarios. |
| #16 |
2025 |
Study synthetic influence group effects on consensus in social networks. |
Visibility and noise shape consensus outcomes; findings inform design of robust digital social systems. |
| #17 |
2025 |
Optimize PBFT consensus strategy for blockchain consortia. |
Review highlights PBFT optimizations for throughput, scaling, and attack resilience. |
| #18 |
2025 |
Secure scalable consensus for multi-agent systems using PBFT/Raft. |
Node grouping and crypto-enhanced consensus lower communication costs while improving security. |
| #19 |
2024 |
Maintain multi-agent consensus under actuator faults with LPV virtual leader model. |
Fault-tolerant observer-controller keeps group formation and task execution even when faults occur. |
| #20 |
2025 |
Enable resilient consensus cluster via a dynamic, event-triggered approach under DoS attacks. |
Reduces message overhead while safeguarding consensus, protecting against unreliable networks and attacks. |
| #21 |
2025 |
Accelerate blockchain consensus with new express Clique approach. |
“ExClique” enables up to 2x-7x faster transaction confirmation than existing Clique-based protocols. |
| #22 |
2025 |
Distribute safe task allocation and motion coordination in networked robot teams. |
Local observation and coordination enable robust task execution across changing multi-robot environments. |
| #23 |
2025 |
Apply deep learning (GNN) in software task deadlock detection. |
Supervised ANN model accurately detects software deadlocks, outperforming classical methods. |
| #24 |
2025 |
Prevent GPU collective communication deadlocks in DL applications. |
“DFCCL” preemption ensures robust, high-performance distributed deep learning. |
| #25 |
2023 |
Use multi-agent deep RL to handle rail network deadlocks. |
Decentralized agents reduce deadlock rates and improve traffic flow through learned policies. |
| #26 |
2025 |
Combine IoT, Petri nets, ANNs for deadlock/tool fault management in flexible manufacturing. |
Enhanced controller improves uptime and productivity by controlling both deadlocks and tool faults. |
| #27 |
2025 |
Prevent robot deadlocks via decentralized, roundabout-based navigation (“Merry-Go-Round”). |
Temporary roundabouts, local peer communication, and preventive intervention avoid standstill. |
| #28 |
2025 |
Optimize distributed, multi-agent navigation via GNN-based graph control. |
Infinite-horizon planning enhances safety and goal-seeking, allowing real-time deadlock avoidance. |
| #29 |
2025 |
Efficient two-layer path planning for WMRs in dynamic environments. |
Combines ACO and dynamic window to generate fast, energy-efficient robot paths in crowded spaces. |
| #30 |
2025 |
Map the service-oriented evolution of modern AI. |
Identifies emerging directions, gaps, and digital transformation drivers in AI service delivery. |
| #31 |
2025 |
Deadlock-free multi-agent pickup/delivery in dynamic, mixed-agent settings. |
Local, reactive collision avoidance policy ensures correct task completion even with external disruptions. |
| #32 |
2025 |
Schedule AGV movement/data processing using extreme-edge computing. |
Joint scheduling maintains system responsiveness and prevents deadlocks through adaptive task allocation. |
| #33 |
2025 |
Promote safe multirobot coordination using distributed, deadlock-aware control. |
Bottleneck detection and navigation priorities preserve team safety and task success. |
| #34 |
2025 |
Use garbage collection liveness for partial deadlock detection/recovery in message-passing programs. |
Dynamic GC marking phase detects and recovers partial deadlocks, reducing memory leaks in Go-style applications. |
| #35 |
2025 |
Theoretical study and solution to deadlocks using “weak deadlock sets.” |
“Wise states” and weak set recognition offer polynomial-time detection and new prevention options in networks. |
| #36 |
2025 |
Plan safe, deadlock-free trajectories for AVs with occlusions and risk constraints. |
Phantom obstacle modeling, risk quantification, and improved planning mitigate AV deadlocks in occluded scenes. |
Table 3.
Application Domain and Technology.
Table 3.
Application Domain and Technology.
| Application Domain |
Technology Used |
Study IDs |
| Manufacturing |
Petri Net, AI |
#5, #13, #26 |
| Blockchain |
Deadlock-Free Routing |
#1, #12, #17 |
Table 4.
System Scope and Strategy.
Table 4.
System Scope and Strategy.
| System Type |
Deadlock Strategy |
Study IDs |
| Cloud/Fog |
Prediction/Prevention |
#11, #24 |
| Multi-Agent |
Consensus-Based |
#18, #22 |
Table 5.
Algorithm Category and Results.
Table 5.
Algorithm Category and Results.
| Algorithm Type |
Key Feature |
Study IDs |
| Graph Neural Net |
Deep Learning |
#23, #28 |
| Game Theoretic |
Decentralized Control |
#25, #27 |
Table 6.
Categorization by Reactive vs Proactive Deadlock Management.
Table 6.
Categorization by Reactive vs Proactive Deadlock Management.
| Strategy |
Description |
Study IDs |
| Proactive |
Methods focusing on predi-ction, avoidance, and preve-ntion of deadlocks before they occur. These include control policies, algorithms for avoi-dance, forecasting, and plan-ning approaches. |
#2, #3, #6, #7, #8, #10, #11, #12, #13, #14, #16, #17, #18, #19, #20, #21, #22, #24, #26, #27, #28, #29, #30, #31, #32, #33, #35, #36 |
| Reactive |
Methods focusing on dete-ction and resolution after deadl-ocks have occurred, such as detection algorithms, recovery techniques, and resolution frameworks. |
#1, #4, #5, #9, #15, #23, #25, #34 |
Limitations of the review
Only studies published in English were included, which may result in missing valuable research published in other languages.
Database & Source Selection: Although the study used several major digital libraries, relevant literature indexed only in other, smaller or regional databases may have been missed.
Publication Bias: Studies with positive results or novel findings are more likely to be published and included, potentially skewing the overall conclusions toward approaches that worked well, while negative or inconclusive results might be underrepresented.
Quality and Heterogeneity of Included Studies: Differences in research methods, scale, datasets, experimental settings, and definitions of ‘deadlock’ across studies can make it difficult to compare findings directly or synthesize results meaningfully.
Time and Resource Constraints: The review window was limited to 2020–2025. Some newer studies may have been missed and resource restrictions may have prevented deeper full-text analysis or expert quality assessment for all retrieved studies.
Rapid Evolution of the Field: AI and distributed systems research evolves extremely quickly; important new approaches, tools, or datasets can be published during or after the review process, leaving gaps in coverage or making some findings quickly outdated.
Limited Experimental Standardization: Benchmarks, metrics, and datasets vary widely. Not all studies used publicly available evaluation frameworks, making comparative analysis challenging and sometimes limiting reproducibility.
Model & Application Diversity: The studies included cover a range of architectures (GNN variants, consensus protocols, reinforcement learning models), application domains (software systems, rail networks, robotics, blockchains), and problem scales. This diversity can complicate cross-study generalization and mean that conclusions apply only to specific settings.
Interpretive Depth: While systematic reviews are powerful for synthesis, they sometimes lack the theoretical insight or nuanced explanation that can be found in detailed primary studies or meta-analyses.
Recommendations
Future reviews should incorporate additional databases and consider studies published in languages other than English to reduce the risk of missing relevant research and minimize language bias.
There is a strong need for widely-accepted experimental benchmarks and datasets tailored to deadlock detection and prevention in distributed systems. This will improve comparability and reproducibility across future studies.
Encourage joint efforts between computer scientists, engineers, and domain experts (such as robotics, networking, AI, and manufacturing) to transfer and adapt best practices and innovative algorithms across different distributed system environments.
Report Negative and Neutral Findings: Journals and conferences in the field should emphasize the importance of publishing negative or inconclusive results. This will provide a complete and unbiased picture of current methods’ capabilities and limitations.
Encourage the sharing of code, datasets, and evaluation scripts. Open-source resources will accelerate the adoption, scrutiny, and iterative improvement of cutting-edge techniques.
Given the rapid evolution of AI and distributed computing, regularly updating systematic reviews or maintaining living documents online will help keep research, industry, and policy efforts aligned with the state-of-the-art.
Future work should include results from large-scale deployments and real-world applications to ensure that proposed algorithms are robust, scalable, and practical under realistic operating conditions.
As GNN and consensus-based models become more complex, integrating interpretable modeling and visualization techniques will help users and stakeholders trust, understand, and troubleshoot AI-driven deadlock management systems.