Parallel ComputingPub Date : 2026-03-01Epub Date: 2025-12-19DOI: 10.1016/j.parco.2025.103182
Sergey Malkovsky, Aleksei Sorokin, Sergey Korolev
{"title":"Analysis of the impact of NUMA node configuration on the performance of offloading computations to GPUs","authors":"Sergey Malkovsky, Aleksei Sorokin, Sergey Korolev","doi":"10.1016/j.parco.2025.103182","DOIUrl":"10.1016/j.parco.2025.103182","url":null,"abstract":"<div><div>The article presents the results of several studies to assess the impact of the configuration of NUMA (Non-Uniform Memory Access) nodes on the performance of GPU-accelerated applications in hybrid computing system with shared memory. Using Crossroads/N9 DGEMM (NVBLAS library) as a model application, the performance in various NUMA modes with one or more GPUs was analyzed, and the throughput of the memory subsystem and data transfer channels between the host memory and graphics processors was also measured. The impact of coprocessor distribution across NUMA nodes on the efficiency of the model application was also examined.</div><div>Results showed that configuration of NUMA nodes can have a significant impact on the performance of applications that offload calculations to graphics coprocessors in a hybrid computing system with shared memory, and this impact could have an effect in different ways. For example, using one NUMA node for the entire computing system is the least optimal approach in terms of memory bandwidth, but it provided the highest bandwidth for communication between host memory and coprocessors during active data transfer to several accelerators. Thus, this mode achieves maximum performance when performing calculations on multiple GPUs that actively exchange data through host memory. Other modes showed advantages in different situations. Overall, to achieve maximum performance during active data transfer to coprocessors, they should be part of one NUMA node. These results will help to develop approaches to configuration of hybrid computing systems on processors with a chiplet layout, and help to improve the performance of software that offloads calculations to graphics accelerators with the Ampere architecture, such as NVIDIA A800 and NVIDIA A100, which are currently widely represented in the high-performance computing industry.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"127 ","pages":"Article 103182"},"PeriodicalIF":2.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2026-03-01Epub Date: 2025-12-05DOI: 10.1016/j.parco.2025.103181
Yubiao Pan, Ailing Tian, Huizhen Zhang
{"title":"PROAD: Boosting Caffe Training via improving LevelDB I/O performance with Parallel Read, Out-of-Order Optimization, and Adaptive Design","authors":"Yubiao Pan, Ailing Tian, Huizhen Zhang","doi":"10.1016/j.parco.2025.103181","DOIUrl":"10.1016/j.parco.2025.103181","url":null,"abstract":"<div><div>Caffe, one of the most popular deep learning frameworks, trains models by reading training data from the storage engine, LevelDB, and feeding it into the computation engine. This paper analyzes the challenges faced by data reading in Caffe Training: (1) Fetch, Parse, and Transform—the three steps of reading each image—are serial, and each image is read sequentially; (2) Frequent disk I/O—each image read triggers an I/O operation—significantly increases the data reading time; (3) Caffe calls LevelDB’s range query method to read training data, but this leads to unnecessary pointer comparison operations, wasting CPU resources; (4) Since LevelDB reads training data in key order during range queries, the fixed order of training data across epochs may cause overfitting and lower the model’s test accuracy.</div><div>Based on these challenges, this paper proposes Parallel Read, Out-of-Order Optimization, and Adaptive Design strategies to design a new I/O layer, PROAD, for Caffe that systematically reconstructs and optimizes LevelDB’s original data reading mechanism, thus improving LevelDB I/O performance for Caffe Training. The Parallel Read method pipelines the Fetch, Parse, and Transform steps and accelerates reading via large block reads; Out-of-Order Optimization discards the range scan feature of LevelDB, allowing Caffe to read training data in a random manner during training, avoiding the original key comparison overhead and providing a boost to model accuracy; while the Adaptive Design method supports efficient reading of training data with different resolutions. Based on these designs, this paper implements PROAD and deploys it in Caffe for performance evaluation. Experimental results show that Caffe with PROAD significantly improves data reading performance during training, especially for high-resolution datasets, where data reading time in Caffe with PROAD is reduced by 14%–42% compared to Caffe with LevelDB and 6%–34% compared to Caffe with LMDB. Furthermore, Caffe with PROAD improves model test accuracy due to the Out-of-Order Optimization strategy, while consuming relatively reasonable memory resources.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"127 ","pages":"Article 103181"},"PeriodicalIF":2.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2026-03-01Epub Date: 2025-12-03DOI: 10.1016/j.parco.2025.103166
Tomas Vondra, David Sebek
{"title":"Benchmark of classical disk array and software-defined storage on near-identical hardware","authors":"Tomas Vondra, David Sebek","doi":"10.1016/j.parco.2025.103166","DOIUrl":"10.1016/j.parco.2025.103166","url":null,"abstract":"<div><div>This article presents a comparative analysis of two storage approaches: a SAN disk array, exemplified by an HPE 3PAR device, and a software-defined storage cluster constructed with the Ceph software. The objective of this comparison is to ascertain whether a software-defined storage cluster built with commodity servers can achieve comparable performance to a SAN disk array with a similar hardware configuration. The configuration used identical numbers of components of matching speeds, capacities, and hardware generation from the same manufacturer. By relaxing some requirements on the software-defined storage, we were able to benchmark all RAID levels with corresponding replication and erasure code settings. The results revealed that 3PAR performed 31 times better for 4 KiB data block writes than Ceph. On the contrary, the Ceph cluster surpassed 3PAR by a factor of 1.4 in 16 MiB large-block reads. The differences are explained in the text based on the theory of operation of the two types of storage. We propose criteria for choosing the correct type of technology for individual use cases.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"127 ","pages":"Article 103166"},"PeriodicalIF":2.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2026-03-01Epub Date: 2025-12-16DOI: 10.1016/j.parco.2025.103168
Kazutomo Yoshii , John R. Tramm , Bryce Allen , Tomohiro Ueno , Kentaro Sano , Andrew Siegel , Pete Beckman
{"title":"A case study in hardware specialization for Monte Carlo cross-section lookup","authors":"Kazutomo Yoshii , John R. Tramm , Bryce Allen , Tomohiro Ueno , Kentaro Sano , Andrew Siegel , Pete Beckman","doi":"10.1016/j.parco.2025.103168","DOIUrl":"10.1016/j.parco.2025.103168","url":null,"abstract":"<div><div>Hardware specialization is a promising direction in the post-Moore era, particularly for high-performance computing (HPC). In this work, we present a lightweight prototyping example of hardware specialization using open-source tools. Focusing on the Monte Carlo cross-section lookup kernel, a computation with low resource utilization on general-purpose architectures, we implement a custom hardware pipeline in Chisel and generate Verilog for resource usage estimation. We explore hardware optimization techniques that trade off throughput and resource usage, and show that, as SRAM scaling stalls and memory dominates chip area, using additional logic, even in brute-force forms, can lead to better overall efficiency. Our estimation demonstrates a significant performance gain over general-purpose CPUs. While this is a case study, the methodology provides a practical path for quick feasibility studies in hardware specialization.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"127 ","pages":"Article 103168"},"PeriodicalIF":2.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146022651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2025-11-01Epub Date: 2025-11-15DOI: 10.1016/j.parco.2025.103164
Motahhare Mirzaei, Mehrdad Ashtiani, Mohammad Javad Pirhadi, Sauleh Eetemadi
{"title":"LSHDP: Locally sharded heterogeneous data parallel for distributed deep learning","authors":"Motahhare Mirzaei, Mehrdad Ashtiani, Mohammad Javad Pirhadi, Sauleh Eetemadi","doi":"10.1016/j.parco.2025.103164","DOIUrl":"10.1016/j.parco.2025.103164","url":null,"abstract":"<div><div>In today’s world, pre-trained models such as GPT-3 and Llama 3.1, along with the use of transformers, recognized as large AI models, have gained significant importance. To accelerate the training of these models, distributed training has become a fundamental approach. This method enables the execution of model training across multiple GPUs, which is particularly essential for models that require more data and training time. Despite past advancements, achieving optimal utilization of GPU capacity remains a major challenge, especially in academic environments that often feature heterogeneous infrastructures and limited bandwidth between nodes, which do not align with the assumptions of existing methods. In previous methods, the node with the lowest computational power is considered the bottleneck, leading to computational slowdowns and increased waiting times for other nodes. This study addresses the issue by adjusting batch sizes to minimize node waiting times. This approach improves the efficiency of node utilization without reducing the convergence speed. Moreover, to address GPU memory limitations, existing methods often rely on high-speed inter-node communication. This reliance increases training time in scenarios with low network bandwidth (e.g., 1 Gb/s). This research mitigates this challenge using the LSDP (Locally Sharded Data Parallel) method, which leverages CPU memory instead of inter-node communication. Finally, by combining these two strategies, the LSHDP (Locally Sharded Heterogeneous Data Parallel) solution is introduced which is suitable for heterogeneous infrastructures with low inter-node communication speeds. Experiments demonstrate that this method outperforms previous approaches in such environments, achieving improvements of 35.39 % and 52.57 % in terms of speed compared to data-parallel and Fully Sharded Data Parallel (FSDP) methods respectively.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"126 ","pages":"Article 103164"},"PeriodicalIF":2.1,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145579261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2025-11-01Epub Date: 2025-10-10DOI: 10.1016/j.parco.2025.103160
Qingke Zhang , Wenliang Chen , Shuzhao Pang , Sichen Tao , Conglin Li , Xin Yin
{"title":"GPU/CUDA-Accelerated gradient growth optimizer for efficient complex numerical global optimization","authors":"Qingke Zhang , Wenliang Chen , Shuzhao Pang , Sichen Tao , Conglin Li , Xin Yin","doi":"10.1016/j.parco.2025.103160","DOIUrl":"10.1016/j.parco.2025.103160","url":null,"abstract":"<div><div>Efficiently solving high-dimensional and complex numerical optimization problems remains a critical challenge in high-performance computing. This paper presents the GPU/CUDA-Accelerated Gradient Growth Optimizer (GGO)—a novel parallel metaheuristic algorithm that combines gradient-guided local search with GPU-enabled large-scale parallelism. Building upon the Growth Optimizer (GO), GGO incorporates a dimension-wise gradient-guiding strategy based on central difference approximations, which improves solution precision without requiring differentiable objective functions. To address the computational bottlenecks of high-dimensional problems, a hybrid CUDA-based framework is developed, integrating both fine-grained and coarse-grained parallel strategies to fully exploit GPU resources and minimize memory access latency. Extensive experiments on the CEC2017 and CEC2022 benchmark suites demonstrate the superior performance of GGO in terms of both convergence accuracy and computational speed. Compared to 49 state-of-the-art optimization algorithms, GGO achieves top-ranked results in 67% of test cases and delivers up to 7.8× speedup over its CPU-based counterpart. Statistical analyses using the Wilcoxon signed-rank test further confirm its robustness across 28 out of 29 functions in high-dimensional scenarios. Additionally, in-depth analysis reveals that GGO maintains high scalability and performance even as the problem dimension and population size increase, providing a generalizable solution for high-dimensional global optimization that is well-suited for parallel computing applications in scientific and engineering domains.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"126 ","pages":"Article 103160"},"PeriodicalIF":2.1,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145271446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2025-11-01Epub Date: 2025-10-29DOI: 10.1016/j.parco.2025.103162
Pedro Moreno , Miguel Areias , Ricardo Rocha
{"title":"A sleek lock-free hash map in an ERA of safe memory reclamation methods","authors":"Pedro Moreno , Miguel Areias , Ricardo Rocha","doi":"10.1016/j.parco.2025.103162","DOIUrl":"10.1016/j.parco.2025.103162","url":null,"abstract":"<div><div>Lock-free data structures have become increasingly significant due to their algorithmic advantages in multi-core cache-based architectures. Safe Memory Reclamation (SMR) is a technique used in concurrent programming to ensure that memory can be safely reclaimed without causing data corruption, dangling pointers, or access to freed memory. The ERA theorem states that any SMR method for concurrent data structures can only provide at most two of the three main desirable properties: Ease of use, Robustness, and Applicability. This fundamental trade-off influences the design of efficient lock-free data structures at an early stage. This work redesigns a previous lock-free hash map to fully exploit the properties of the ERA theorem and to leverage the characteristics of multi-core cache-based architectures by minimizing the number of cache misses, which are a significant bottleneck in multi-core environments. Experimental results show that our design outperforms the previous design, which was already quite competitive when compared against the Concurrent Hash Map design of the Intel’s TBB library.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"126 ","pages":"Article 103162"},"PeriodicalIF":2.1,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parallel ComputingPub Date : 2025-11-01Epub Date: 2025-11-06DOI: 10.1016/j.parco.2025.103163
Athanasios Margaris , Stavros Souravlas
{"title":"Detecting chaotic regions of recurrent equations in parallel environments","authors":"Athanasios Margaris , Stavros Souravlas","doi":"10.1016/j.parco.2025.103163","DOIUrl":"10.1016/j.parco.2025.103163","url":null,"abstract":"<div><div>This paper investigates how parallel computing techniques, such as OpenMP and CUDA, can be optimized to enhance the computational efficiency of detecting chaotic regions in the parameter space of recurrent equations, a critical task in chaos theory. Leveraging the embarrassingly parallel nature of maximum Lyapunov exponent calculations, our method targets systems with known recurrence relations, where governing equations are analytically defined. Applied to a discretized recurrent neural model, the proposed approach achieves significant speedups, addressing the computational intensity of chaos detection. While building on established parallel techniques, this work fills a gap in their systematic application to chaos detection in high-dimensional systems, offering a scalable solution with potential for real-time analysis. We provide detailed performance metrics, parallel I/O guidelines, and visualization strategies, demonstrating adaptability to other analytically defined chaotic systems.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"126 ","pages":"Article 103163"},"PeriodicalIF":2.1,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145528562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A dependency-aware task offloading in IoT-based edge computing system using an optimized deep learning approach","authors":"Shiva Shankar Reddy , Silpa Nrusimhadri , Gadiraju Mahesh , Veeranki Venkata Rama Maheswara Rao","doi":"10.1016/j.parco.2025.103161","DOIUrl":"10.1016/j.parco.2025.103161","url":null,"abstract":"<div><div>Internet of Things (IoT) devices produce a lot of data, which can be difficult to process on limited computing systems. Edge computing aims to solve this issue by providing localized processing power at the edge of IoT networks to reduce communication delays and network bandwidth. Because of their limited resources and task dependencies, edge computing systems are facing computational issues as a result of the growing usage of IoT devices. An efficient task-offloading system that combines the Fire Hawk Optimizer (FHO) and Deep Reinforcement Learning (DRL) is proposed in this research to address these issues. This paper proposes leveraging deep learning techniques to prioritize and offload computational tasks from IoT applications to edge computing systems, addressing task interdependencies and resource constraints to enhance efficiency. The proposed method consists of two components. The first component uses Petri-Net modelling to analyze interdependencies among tasks, identify subtasks, and map their relationships. The second component uses a residual neural network-based actor-critic deep reinforcement learning (ResNet-ACDRL) decision-making model to offload tasks. Task dependencies and resource availability are assessed by the DRL component, namely a ResNet-ACDRL model, which is utilized to dynamically learn and enhance task-offloading strategies. In order to ensure optimal task allocation across local, edge, and cloud computing resources, the FHO is then used to refine these learned policies. Here, the term \"policy\" refers to the strategy used by the system to decide the most suitable resource for task execution. This dual approach strategy drastically reduces energy usage and execution delays. The suggested framework outperforms existing methods, according to experimental data, especially when managing task interdependencies and a variety of computational loads. The proposed method has been shown to significantly improve time delay and energy consumption compared to existing methods.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"126 ","pages":"Article 103161"},"PeriodicalIF":2.1,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Using Java to create and analyze models of parallel computing systems","authors":"Harish Padmanaban , Nurkasym Arkabaev , Maher Ali Rusho , Vladyslav Kozub , Yurii Kozub","doi":"10.1016/j.parco.2025.103146","DOIUrl":"10.1016/j.parco.2025.103146","url":null,"abstract":"<div><div>The purpose of the study is to develop optimal solutions for models of parallel computing systems using the Java language. During the study, programs were written for the examined models of parallel computing systems. The result of the parallel sorting code is the output of a sorted array of random numbers. When processing data in parallel, the time spent on processing and the first elements of the list of squared numbers are displayed. When processing requests asynchronously, processing completion messages are displayed for each task with a slight delay. The main results include the development of optimization methods for algorithms and processes, such as the division of tasks into subtasks, the use of non-blocking algorithms, effective memory management, and load balancing, as well as the construction of diagrams and comparison of these methods by characteristics, including descriptions, implementation examples, and advantages. In addition, various specialized libraries were analyzed to improve the performance and scalability of the models. The results of the work performed showed a substantial improvement in response time, bandwidth, and resource efficiency in parallel computing systems. Scalability and load analysis assessments were conducted, demonstrating how the system responds to an increase in data volume or the number of threads. Profiling tools were used to analyze performance in detail and identify bottlenecks in models, which improved the architecture and implementation of parallel computing systems. The obtained results emphasize the importance of choosing the right methods and tools for optimizing parallel computing systems, which can substantially improve their performance and efficiency.</div></div>","PeriodicalId":54642,"journal":{"name":"Parallel Computing","volume":"125 ","pages":"Article 103146"},"PeriodicalIF":2.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}