Demo Data from EDBT 2026 / reviewers in the wild / expert
Alok Prakash
dblp:58/7646
· DBLP profile ↗
28ranked-venue papers
6as first author
5since 2021 · last 2025
0000-0001-8257-2974ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Systems, architecture and hardware · 20 · 6 first-author · 1 since 2021Artificial intelligence and machine learning · 4 · 3 since 2021Software engineering, systems software and programming languages · 2Graphics, computer vision, multimedia, augmented reality and games · 2Applied, interdisciplinary, general and emerging computing · 1
Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.
| Artificial intelligence
3 papers |
Efficient and distributed learning · 30% Language models and text generation · 28% Trustworthy machine learning · 26% | |
| Computer architecture, parallel and distributed computing, and storage systems
6 papers |
Energy-efficient computing · 40% Electronic design automation · 26% GPUs and heterogeneous computing · 20% |
Topics — the 20 heaviest of 23, each with the papers that count most for it
| Topic | Weight | Papers | Last | Evidence papers |
|---|---|---|---|---|
Machine learning › Efficient and distributed learning
inference efficiency |
0.9 | 1 | 2025 | TETRIS: Optimal Draft Token Selection for Batch Speculative Decoding · ACL (1) 2025 |
Machine learning › Efficient and distributed learning › inference acceleration
speculative decoding |
0.9 | 1 | 2025 | TETRIS: Optimal Draft Token Selection for Batch Speculative Decoding · ACL (1) 2025 |
Natural language and speech › Language models and text generation
text generation |
0.9 | 1 | 2025 | TETRIS: Optimal Draft Token Selection for Batch Speculative Decoding · ACL (1) 2025 |
Natural language and speech › Language models and text generation
in-context learning |
0.8 | 1 | 2024 | DETAIL: Task DEmonsTration Attribution for Interpretable In-context Learning · NeurIPS 2024 |
Machine learning › Trustworthy machine learning › interpretability › training data attribution
influence function |
0.8 | 1 | 2024 | DETAIL: Task DEmonsTration Attribution for Interpretable In-context Learning · NeurIPS 2024 |
Machine learning › Trustworthy machine learning
interpretability |
0.8 | 1 | 2024 | DETAIL: Task DEmonsTration Attribution for Interpretable In-context Learning · NeurIPS 2024 |
Electronic design automation › physical design › placement
module placement |
0.5 | 1 | 2021 | Power-Efficient Mapping of Large Applications on Modern Heterogeneous FPGAs · IEEE Trans. Comput. Aided Des. Integr. Circuits Syst. 2021 |
GPUs and heterogeneous computing
CPU-GPU heterogeneous computing |
0.4 | 1 | 2020 | Collaborative Adaptation for Energy-Efficient Heterogeneous Mobile SoCs · IEEE Trans. Computers 2020 |
GPUs and heterogeneous computing › CPU-GPU heterogeneous computing
CPU-GPU heterogeneous systems |
0.2 | 1 | 2016 | Improving mobile gaming performance through cooperative CPU-GPU thermal management · DAC 2016 |
Electronic design automation
design space exploration |
0.2 | 1 | 2016 | Lin-analyzer: a high-level performance analysis tool for FPGA-based accelerators · DAC 2016 |
Energy-efficient computing › thermal management
dynamic thermal management |
0.2 | 1 | 2016 | Improving mobile gaming performance through cooperative CPU-GPU thermal management · DAC 2016 |
Reconfigurable computing and FPGAs
FPGA accelerator |
0.2 | 1 | 2016 | Lin-analyzer: a high-level performance analysis tool for FPGA-based accelerators · DAC 2016 |
Electronic design automation
high-level synthesis |
0.2 | 1 | 2016 | Lin-analyzer: a high-level performance analysis tool for FPGA-based accelerators · DAC 2016 |
Energy-efficient computing
thermal management |
0.2 | 1 | 2016 | Improving mobile gaming performance through cooperative CPU-GPU thermal management · DAC 2016 |
Energy-efficient computing
power-performance modeling |
0.2 | 1 | 2015 | Power-Performance Modelling of Mobile Gaming Workloads on Heterogeneous MPSoCs · DAC 2015 |
Embedded and real-time systems › embedded hardware platform
mobile system-on-chip |
0.2 | 2 | 2020 | Collaborative Adaptation for Energy-Efficient Heterogeneous Mobile SoCs · IEEE Trans. Computers 2020 Improving mobile gaming performance through cooperative CPU-GPU thermal management · DAC 2016 |
Energy-efficient computing › power management
dynamic voltage and frequency scaling |
0.2 | 1 | 2014 | Integrated CPU-GPU Power Management for 3D Mobile Games · DAC 2014 |
Energy-efficient computing
power management |
0.2 | 1 | 2014 | Integrated CPU-GPU Power Management for 3D Mobile Games · DAC 2014 |
Embedded and real-time systems › embedded hardware platform › MPSoC
heterogeneous MPSoC |
0.1 | 1 | 2015 | Power-Performance Modelling of Mobile Gaming Workloads on Heterogeneous MPSoCs · DAC 2015 |
GPUs and heterogeneous computing
CPU-GPU power management |
0.1 | 1 | 2014 | Integrated CPU-GPU Power Management for 3D Mobile Games · DAC 2014 |
Methods — techniques the papers use, named apart from their topics
optimization · 0.9elo rating · 0.9competitive interaction modeling · 0.9influence functions · 0.8demonstration reordering · 0.8attribution · 0.8module splitting · 0.5module locking · 0.5runtime adaptation · 0.4OpenCL · 0.4performance analysis · 0.2design space exploration · 0.2control theory · 0.2power-performance modeling · 0.2dynamic voltage/frequency scaling · 0.2
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | TETRIS: Optimal Draft Token Selection for Batch Speculative DecodingabstractZhaoxuan Wu, Zijian Zhou, Arun Verma, Alok Prakash, Daniela Rus, Bryan Kian Hsiang Low. Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers). 2025. Zhaoxuan Wu, Zijian Zhou 0006, Arun Verma, Alok Prakash, Daniela Rus, Kian Hsiang Low |
ACL (1) | 4 |
| 2025 | AGI-Elo: How Far Are We From Mastering A Task?abstractAs the field progresses toward Artificial General Intelligence (AGI), there is a pressing need for more comprehensive and insightful evaluation frameworks that go beyond aggregate performance metrics. This paper introduces a unified rating system that jointly models the difficulty of individual test cases and the competency of AI models (or humans) across vision, language, and action domains. Unlike existing metrics that focus solely on models, our approach allows for fine-grained, difficulty-aware evaluations through competitive interactions between models and tasks, capturing both the long-tail distribution of real-world challenges and the competency gap between current models and full task mastery. We validate the generalizability and robustness of our system through extensive experiments on multiple established datasets and models across distinct AGI domains. The resulting rating distributions offer novel perspectives and interpretable insights into task difficulty, model progression, and the outstanding challenges that remain on the path to achieving full AGI task mastery. We have made our code and results publicly available at https://ss47816.github.io/AGI-Elo/. Shuo Sun 0002, Christina E. Lee, Jiawei Sun 0006, Chengran Yuan, Zefan Huang, Dongen Li, Justin KW Yeoh, Alok Prakash, Thomas W. Malone, Marcelo H. Ang |
NeurIPS | 9 |
| 2024 | DETAIL: Task DEmonsTration Attribution for Interpretable In-context LearningabstractIn-context learning (ICL) allows transformer-based language models that are pre-trained on general text to quickly learn a specific task with a few "task demonstrations" without updating their parameters, significantly boosting their flexibility and generality. ICL possesses many distinct characteristics from conventional machine learning, thereby requiring new approaches to interpret this learning paradigm. Taking the viewpoint of recent works showing that transformers learn in context by formulating an internal optimizer, we propose an influence function-based attribution technique, DETAIL, that addresses the specific characteristics of ICL. We empirically verify the effectiveness of our approach for demonstration attribution while being computationally efficient. Leveraging the results, we then show how DETAIL can help improve model performance in real-world scenarios through demonstration reordering and curation. Finally, we experimentally prove the wide applicability of DETAIL by showing our attribution scores obtained on white-box models are transferable to black-box models in improving model performance. Zijian Zhou 0006, Xiaoqiang Lin, Alok Prakash, Daniela Rus, Kian Hsiang Low |
NeurIPS | 4 |
| 2021 | I2UTS: An IoT based Intelligent Urban Traffic SystemabstractGrowing population and migration to cities have given birth to multiple urban issues. Traffic congestion is one of the most prominent ones with severe side effects like fuel wastage, loss of lives, and slow productivity. The traditional traffic control system deploys programming logic control (PLC) which uses round-robin scheduling algorithm. However, few recent works have proposed IoT-based framework which requires the deployment of a series of sensors. In this paper, we propose an IoT-based framework that uses the existing network of CCTV cameras at the junction. An edge device is used to estimate the traffic density and detect emergency vehicles using YOLO v3 -Efficient Net. These two parameters are used as an input to a novel traffic control algorithm. The performance of the proposed framework has been evaluated by analyzing its properties using the UA-DETRAC dataset. The proposed framework achieves 68.10% vehicle detection accuracy. Vejey Pradeep Suresh Achari, Zeba Khanam, Amit Kumar Singh 0002, Anish Jindal, Alok Prakash, Neeraj Kumar 0001 |
HPSR | 5 |
| 2021 | Power-Efficient Mapping of Large Applications on Modern Heterogeneous FPGAsabstractThe increasing size of modern field programmable gate arrays (FPGAs) allows for ever more complex applications to be mapped onto them. However, long design implementation times for large designs can severely affect design productivity. A modular design methodology can improve design productivity in a divide and conqueror fashion but at the expense of degraded performance and power consumption of the resulting implementation. To reduce the dominant power dissipation component in FPGAs, the routing power, methodologies have been proposed that consider data communication between modules during module formation and placement on the FPGA. Selecting proper mapping region on target FPGAs, on the other hand, is becoming a critical process because of the heterogeneous resources and column arrangements in modern FPGAs. Selecting inappropriate FPGA regions for mapping could lead to degraded performance. Hence, we propose a methodology that uses communication-aware module placement, such that modules are mapped by selecting the best shape and region on the FPGA factoring the columnar resource arrangements. Additionally, techniques for module locking and splitting have been proposed for deterministic convergence of the algorithm and for improved module placement. This methodology exhibits nearly 19% routing power reduction with respect to commercial CAD flows without any degradation in achievable performance. Kalindu Herath, Alok Prakash, Suhaib A. Fahmy, Thambipillai Srikanthan |
IEEE Trans. Comput. Aided Des. Integr. Circuits Syst. | 2 |
| 2020 | Evaluating the Merits of Ranking in Structured Network PruningabstractPruning of channels in trained deep neural networks has been widely used to implement efficient DNNs that can be deployed on embedded/mobile devices. Majority of existing techniques employ criteria-based sorting of the channels to preserve salient channels during pruning as well as to automatically determine the pruned network architecture. However, recent studies on widely used DNNs, such as VGG-16, have shown that selecting and preserving salient channels using pruning criteria is not necessary since the plasticity of the network allows the accuracy to be recovered through fine-tuning. In this work, we further explore the value of the ranking criteria in pruning to show that if channels are removed gradually and iteratively, alternating with fine-tuning on the target dataset, ranking criteria are indeed not necessary to select redundant channels. Experimental results confirm that even a random selection of channels for pruning leads to similar performance (accuracy). In addition, we demonstrate that even a simple pruning technique that uniformly removes channels from all layers in the network, performs similar to existing ranking criteria-based approaches, while leading to lower inference time (GFLOPs). Our extensive evaluations include the context of embedded implementations of DNNs - specifically, on small networks such as SqueezeNet and at aggressive pruning percentages. We leverage these insights, to propose a GFLOPs-aware iterative pruning strategy that does not rely on any ranking criteria and yet can further lead to lower inference time by 15% without sacrificing accuracy. Nirmala Ramakrishnan, Alok Prakash, Siew-Kei Lam, Thambipillai Srikanthan |
ICDCS | 3 |
| 2020 | Collaborative Adaptation for Energy-Efficient Heterogeneous Mobile SoCsabstractHeterogeneous Mobile System-on-Chips (SoCs) containing CPU and GPU cores are becoming prevalent in embedded computing, and they need to execute applications concurrently. However, existing run-time management approaches do not perform adaptive mapping and thread-partitioning of applications while exploiting both CPU and GPU cores at the same time. In this paper, we propose an adaptive mapping and thread-partitioning approach for energy-efficient execution of concurrent OpenCL applications on both CPU and GPU cores while satisfying performance requirements. To start execution of concurrent applications, the approach makes mapping (number of cores and operating frequencies) and partitioning (distribution of threads between CPU and GPU) decisions to satisfy performance requirements for each application. The mapping and partitioning decisions are made by having a collaboration between the CPU and GPU cores' processing capabilities such that balanced execution can be performed. During execution, adaptation is triggered when new application(s) arrive, or an executing one finishes, that frees cores. The adaptation process identifies a new mapping and thread-partitioning in a similar collaborative manner for remaining applications provided it leads to an improvement in energy efficiency. The proposed approach is experimentally validated on the Odroid-XU3 hardware platform with varying set of applications. Results show an average energy saving of 37%, compared to existing approaches while satisfying the performance requirements. Amit Kumar Singh 0002, Basireddy Karunakar Reddy, Alok Prakash, Geoff V. Merrett, Bashir M. Al-Hashimi |
IEEE Trans. Computers | 3 |
| 2020 | Rapid and Robust Background Modeling Technique for Low-Cost Road Traffic Surveillance SystemsabstractFast and accurate detection of vehicles on road traffic scenes captured by traffic surveillance cameras, is essential for large-scale deployment of automated traffic surveillance systems. The state-of-the-art techniques typically employ background modeling for low-complexity foreground detection. However, this is a challenging problem as these methods need to be robust to varying road scene conditions (such as illumination changes, camera jitter, stationary vehicles, and heavy traffic) leading to huge computation cost. In this paper, we propose a highly accurate yet low-complexity foreground (i.e., vehicle) detection technique, which can effectively deal with the varying road scene conditions, and generate accurate pixel-level foreground masks in real-time. We propose a novel robust block-based feature suitable for modeling road background and detecting vehicles as foreground, and employ Bayesian probabilistic modeling on these features. The experimental evaluations on widely used traffic datasets demonstrate that the proposed method can achieve comparable accuracy to the existing state-of-the-art techniques but at a much higher processing frame rate (40x speedup over PAWCS). The real-time performance of the proposed system has also been demonstrated by implementing it on a low-cost embedded platform, Odroid XU-4, that still achieves a frame rate of over 80 frames/s, thereby enabling the real-time detection of foreground objects in road scenes. Kratika Garg, Nirmala Ramakrishnan, Alok Prakash, Thambipillai Srikanthan |
IEEE Trans. Intell. Transp. Syst. | 3 |
| 2019 | Rapid Technique to Eliminate Moving Shadows for Accurate Vehicle DetectionabstractElimination of moving shadows is an essential step to achieve accurate vehicle detection and localization in automated traffic surveillance systems that aim to detect vehicles on road scenes captured by surveillance cameras. However, this is still a challenging problem as existing pixel based methods miss parts of vehicles and region-based methods, while accurate, incur higher computations. In this paper, we propose a highly accurate yet low-complexity block-based moving shadow elimination technique, which can effectively deal with varying shadow conditions. A novel shadow elimination pipeline is proposed that employs computationally lean features to quickly classify distinct vehicles from shadows, and uses a more sophisticated interior edge feature only for classification of difficult scenarios. Extensive evaluations on freely available and self-collected datasets demonstrate that the proposed technique achieves higher accuracy than other state-of-the-art techniques in varying scenarios. Additionally, it also achieves over 20 times speedup on a low-cost embedded platform, Odroid XU-4, over a state-of-the-art technique that achieves comparable accuracy. Experimental results confirm the realtime capability of the proposed approach while achieving robustness to varying shadow scenarios. Kratika Garg, Nirmala Ramakrishnan, Alok Prakash, Thambipillai Srikanthan, Punit Bhatt |
WACV | 3 |
| 2018 | Wibheda: Framework for Data Dependency-Aware Multi-Constrained Hardware-Software Partitioning in FPGA-Based SoCs for IoT DevicesabstractThe increasing popularity of FPGA-based system-on-chip (SoC) devices for Internet of Things (IoT) applications calls for hardware-software partitioning solutions optimized for performance under stringent area and power constraints. In this work, we propose Wibheda, a heuristic based framework for data dependency-aware multi-constrained hardware-software partitioning at fine-granularity that can be employed to partition designs for FPGA-based SoCs used in IoT. Wibheda, evaluated on 6 applications from the popular CHStone benchmark suite has been shown to find solutions with 98.7% accuracy within several milliseconds compared to several minutes or hours in an existing state-of-the-art work and an exhaustive approach respectively. Deshya Wijesundera, Alok Prakash, Thilina Perera, Kalindu Herath, Thambipillai Srikanthan |
FCCM | 2 |
| 2018 | A Hybrid Methodology for Optimal Fleet Management in an Electric Vehicle Based Flexible Bus ServiceabstractThe ever-increasing traffic congestion and CO2emission caused by rapid urbanization, calls for smarter and energy efficient transit services. Conventional public transit lacks the ability to meet these diversified needs. As a result, intelligent transit systems, influenced by the digital revolution have created a profound impact by enhancing the user-experience of transit services. Consequently, demand responsive transit (DRT) services, which operate with flexible routes and schedules have become a common option among commuters. Thus, in this work, we propose an electric vehicle (EV) based flexible bus service, a variant of DRT, that satisfies passenger demand in a given geographical zone. Next, we present a hybrid methodology to optimally manage the EV fleet minimizing the total vehicle miles travelled (VMT). Experimental results with a real map show that the proposed hybrid method achieves near-optimal results with 120x improvement in computation time. Further, the flexible bus service reduces VMT by over 70% in comparison to single occupancy vehicles, thus reducing both traffic congestion and CO2emissions. Thilina Perera, Alok Prakash, Thambipillai Srikanthan |
ICARCV | 2 |
| 2018 | Framework for Rapid Performance Estimation of Embedded Soft Core ProcessorsabstractThe large number of embedded soft core processors available today make it tedious and time consuming to select the best processor for a given application. This task is even more challenging due to the numerous configuration options available for a single soft core processor while optimizing for contradicting design requirements such as performance and area. In this article, we propose a generic framework for rapid performance estimation of applications on soft core processors. The proposed technique is scalable to the large number of configuration options available in modern soft core processors by relying on rapid and accurate estimation models instead of time-consuming FPGA synthesis and execution-based techniques. Experimental results on two leading commercial soft core processors executing applications from the widely used CHStone benchmark suite show an average error of less than 6% while running in the order of minutes when compared to hours taken by synthesis-based techniques. Deshya Wijesundera, Alok Prakash, Thambipillai Srikanthan, Achintha Ihalage |
ACM Trans. Reconfigurable Technol. Syst. | 2 |
| 2018 | Rapid Memory-Aware Selection of Hardware Accelerators in Programmable SoC DesignabstractProgrammable Systems-on-Chips (SoCs) are expected to incorporate a larger number of application-specific hardware accelerators with tightly integrated memories in order to meet stringent performance-power requirements of embedded systems. As data sharing between the accelerator memories and the processor is inevitable, it is of paramount importance that the selection of application segments for hardware acceleration must be undertaken such that the communication overhead of data transfers do not impede the advantages of the accelerators. In this paper, we propose a novel memory-aware selection algorithm that is based on an iterative approach to rapidly recommend a set of hardware accelerators that will provide high performance gain under varying area constraint. In order to significantly reduce the algorithm runtime while still guaranteeing near-optimal solutions, we propose a heuristic to estimate the penalties incurred when the processor accesses the accelerator memories. In each iteration of the proposed algorithm, a two-pass method is employed where a set of good hardware accelerator candidates is selected using a greedy approach in the first pass, and a “sliding window” approach is used in the second pass to refine the solution. The two-pass method is iteratively performed on a bounded set of candidate hardware accelerators to limit the search space and to avoid local maxima. In order to validate the benefits of the proposed selection algorithm, an exhaustive search algorithm is also developed. Experimental results using the popular CHStone benchmark suite show that the performance achieved by the accelerators recommended by the proposed algorithm closely matches the performance of the exhaustive algorithm, with close to 99% accuracy, while being orders of magnitude faster. Alok Prakash, Christopher T. Clarke, Siew-Kei Lam, Thambipillai Srikanthan |
IEEE Trans. Very Large Scale Integr. Syst. | 1 |
| 2017 | Secure Cyber-Physical Systems: Current trends, tools and open research problemsabstractTo understand and identify the attack surfaces of a Cyber-Physical System (CPS) is an essential step towards ensuring its security. The growing complexity of the cybernetics and the interaction of independent domains such as avionics, robotics and automotive is a major hindrance against a holistic view CPS. Furthermore, proliferation of communication networks have extended the reach of CPS from a user-centric single platform to a widely distributed network, often connecting to critical infrastructure, e.g., through smart energy initiative. In this manuscript, we reflect on this perspective and provide a review of current security trends and tools for secure CPS. We emphasize on both the design and execution flows and particularly highlight the necessity of efficient attack surface detection. We provide a detailed characterization of attacks reported on different cyber-physical systems, grouped according to their application domains, attack complexity, attack source and impact. Finally, we review the current tools, point out their inadequacies and present a roadmap of future research. Anupam Chattopadhyay, Alok Prakash, Muhammad Shafique 0001 |
DATE | 2 |
| 2017 | Design Space exploration of FPGA-based accelerators with multi-level parallelismabstractApplications containing compute-intensive kernels with nested loops can effectively leverage FPGAs to exploit fine-and coarse-grained parallelism. HLS tools used to translate these kernels from high-level languages (e.g., C/C--), however, are inefficient in exploiting multiple levels of parallelism automatically, thereby producing sub-optimal accelerators. Moreover, the large design space resulting from the various combinations of fineand coarse-grained parallelism options makes exhaustive design space exploration prohibitively time-consuming with HLS tools. Hence, we propose a rapid estimation framework, MPSeeker, to evaluate performance/area metrics of various accelerator options for an application at an early design phase. Experimental results show that MPSeeker can rapidly (in minutes) explore the complex design space and accurately estimate performance/area of various design points to identify the near-optimal (95.7% performance of the optimal on average) combination of parallelism options. Guanwen Zhong, Alok Prakash, Yun Liang 0001, Tulika Mitra, Smaïl Niar |
DATE | 2 |
| 2017 | Communication-aware Partitioning for Energy Optimization of Large FPGA DesignsabstractModern FPGAs integrate multi-million logic resources that allow the realization of increasingly large designs. However, state-of-the-art simulated annealing based CAD tools for FPGA suffer from long runtime, poor performance and sub-optimal routing and placement decisions, especially for large applications, leading to less energy efficient designs. In this paper, we present a partitioning methodology that divides large application into smaller subsystems based on the communication frequency between these subsystems. We leverage the existing CAD tools to compile the large design, which is now annotated with their subsystems, to obtain the final bitstream. Experiments show that the proposed strategy can lead to a performance gain of over 60% while still achieving more than 20% reduction in energy consumption. Kalindu Herath, Alok Prakash, Guiyuan Jiang, Thambipillai Srikanthan |
ACM Great Lakes Symposium on VLSI | 2 |
| 2017 | Energy-Efficient Run-Time Mapping and Thread Partitioning of Concurrent OpenCL Applications on CPU-GPU MPSoCsabstractHeterogeneous Multi-Processor Systems-on-Chips (MPSoCs) containing CPU and GPU cores are typically required to execute applications concurrently. However, as will be shown in this paper, existing approaches are not well suited for concurrent applications as they are developed either by considering only a single application or they do not exploit both CPU and GPU cores at the same time. In this paper, we propose an energy-efficient run-time mapping and thread partitioning approach for executing concurrent OpenCL applications on both GPU and GPU cores while satisfying performance requirements. Depending upon the performance requirements, for each concurrently executing application, the mapping process finds the appropriate number of CPU cores and operating frequencies of CPU and GPU cores, and the partitioning process identifies an efficient partitioning of the applications’ threads between CPU and GPU cores. We validate the proposed approach experimentally on the Odroid-XU3 hardware platform with various mixes of applications from the Polybench benchmark suite. Additionally, a case-study is performed with a real-world application SLAMBench. Results show an average energy saving of 32% compared to existing approaches while still satisfying the performance requirements. Amit Kumar Singh 0002, Alok Prakash, Basireddy Karunakar Reddy, Geoff V. Merrett, Bashir M. Al-Hashimi |
ACM Trans. Embed. Comput. Syst. | 2 |
| 2016 | Improving mobile gaming performance through cooperative CPU-GPU thermal managementabstractState-of-the-art thermal management techniques independently throttle the frequencies of high-performance multi-core CPU and powerful graphics processing units (GPU) on heterogeneous multiprocessor system-on-chips deployed in latest mobile devices. For graphics-intensive gaming applications, this approach is inadequate because both the CPU and the GPU contribute towards the overall application performance (frames per second or FPS) as well as the on-chip temperature. The lack of coordination between CPU and GPU induces recurrent frequency throttling to maintain on-chip temperature below the permissible limit. This leads to significantly degraded application performance and large variation in temperature over time. We propose a control-theory based dynamic thermal management technique that cooperatively scales CPU and GPU frequencies to meet the thermal constraint while achieving high performance for mobile gaming. Experimental results with six popular Android games on a commercial mobile platform show an average 19% performance improvement and over 90% reduction in temperature variance compared to the original Linux approach. Alok Prakash, Hussam Amrouch, Muhammad Shafique 0001, Tulika Mitra, Jörg Henkel |
DAC | 1 |
| 2016 | Lin-analyzer: a high-level performance analysis tool for FPGA-based acceleratorsabstractThe increasing complexity of FPGA-based accelerators, coupled with time-to-market pressure, makes high-level synthesis (HLS) an attractive solution to improve designer productivity by abstracting the programming effort above register-transfer level (RTL). HLS offers various architectural design options with different trade-offs via pragmas (loop unrolling, loop pipelining, array partitioning). However, non-negligible HLS runtime renders manual or automated HLS-based exhaustive architectural exploration practically infeasible. To address this challenge, we present Lin-Analyzer, a high-level accurate performance analysis tool that enables rapid design space exploration with various pragmas for FPGA-based accelerators without requiring RTL implementations. Guanwen Zhong, Alok Prakash, Yun Liang 0001, Tulika Mitra, Smaïl Niar |
DAC | 2 |
| 2016 | Rapid design space exploration for soft core processor customization and selectionabstractThe large number of soft core processors available today make it challenging to select the best processor for a given application. This issue is further exacerbated by the numerous configuration options available for soft core processors while customizing for contradictory design requirements such as performance and area. In this paper, we propose a framework for rapid application-specific soft core processor customization as well as selection to achieve best performance within user-specified area constraint. The proposed technique is scalable to the large number of configuration options available in modern soft core processors by relying on rapid and accurate estimation models instead of time consuming FPGA synthesis and execution steps. Experimental results on two leading commercial soft core processors executing applications from the popular CHStone benchmark suite show over 93% accuracy in processor performance estimation, completed in order of seconds, leading to a rapid and reliable soft core processor customization and selection. Deshya Wijesundera, Alok Prakash, Thambipillai Srikanthan |
FPT | 2 |
| 2016 | Exploiting Configuration Dependencies for Rapid Area-efficient Customization of Soft-core ProcessorsabstractThe large number of possible configurations in modern soft-core processors make it tedious and time consuming to select the optimal configuration for a given application. In this paper, we propose a framework for rapid area-efficient customization of soft-core processors that exploits the dependencies between the various configuration options to prune the design space. Additionally, the proposed technique relies on rapid and accurate estimation models instead of the time consuming synthesis and execution techniques proposed in the existing work. Experimental results based on hand-coded applications and applications from the popular CHStone benchmark suite show that the proposed framework can rapidly and reliably select the best processor configuration for a given application and save an average of 47.58% area over the processor with all the configuration options enabled while achieving similar performance. Deshya Wijesundera, Alok Prakash, Siew-Kei Lam, Thambipillai Srikanthan |
SCOPES | 2 |
| 2015 | Power-Performance Modelling of Mobile Gaming Workloads on Heterogeneous MPSoCs
Anuj Pathania, Alexandru Eugen Irimiea, Alok Prakash, Tulika Mitra |
DAC | 3 |
| 2015 | Energy-efficient execution of data-parallel applications on heterogeneous mobile platformsabstractState-of-the-art mobile system-on-chips (SoC) include heterogeneity in various forms for accelerated and energy-efficient execution of diverse range of applications. The modern SoCs now include programmable cores such as CPU and GPU with very different functionality. The SoCs also integrate performance heterogeneous cores with different power-performance characteristics but the same instruction-set architecture such as ARM big.LITTLE. In this paper, we first explore and establish the combined benefits of functional heterogeneity and performance heterogeneity in improving power-performance behavior of data parallel applications. Next, given an application specified in OpenCL, we present a static partitioning strategy to execute the application kernel across CPU and GPU cores along with voltage-frequency setting for individual cores so as to obtain the best power-performance tradeoff. We achieve over 19% runtime improvement by exploiting the functional and performance heterogeneities concurrently. In addition, energy saving of 36% is achieved by using appropriate voltage-frequency setting without significantly degrading the runtime improvement from concurrent execution. Alok Prakash, Alexandru Eugen Irimiea, Tulika Mitra |
ICCD | 1 |
| 2014 | Integrated CPU-GPU Power Management for 3D Mobile GamesabstractModern system-on-chips (SoC) integrate CPU and GPU for immersive 3D gaming experience. These games require both the CPU and GPU to work in tandem, resulting in high power consumption. In the past, Dynamic Voltage Frequency Scaling (DVFS) has been exploited for embedded CPU to save power during game play; but it is only recently that embedded GPUs have attained DVFS capabilities that provide additional opportunities. In this paper, we propose a power management approach that takes a unified view of the CPU-GPU DVFS, resulting in reduced power consumption for latest 3D mobile games compared to an independent CPU-GPU power management approach. Anuj Pathania, Qing Jiao, Alok Prakash, Tulika Mitra |
DAC | 3 |
| 2013 | Modelling communication overhead for accessing local memories in hardware acceleratorsabstractLocal memories increase the efficiency of hardware accelerators by enabling fast accesses to frequently used data. In addition, the access latencies of local memories are deterministic which allows for more accurate evaluation of the system performance during design exploration. We have previously proposed local memories with an un-cached memory slave interface that permits program running on the processor to access the locally stored variables in the hardware accelerator. While this has relaxed the memory constraints for porting code sections to hardware accelerators, there is now a need to consider the read/write access penalties of local memories from the processor during design exploration. In order to facilitate the selection of profitable hardware accelerators, we need an accurate performance model that takes into account these read/write access penalties. In this paper, we propose a novel model to estimate the penalty incurred due to memory dependencies between the program running on the processor and the local memories in the FPGA hardware accelerator. This model can be used in an automated design exploration framework for heterogeneous FPGA platforms to select profitable hardware accelerators with local memories. Alok Prakash, Siew-Kei Lam, Thambipillai Srikanthan, Christopher T. Clarke |
ASAP | 1 |
| 2012 | Custom instructions with local memory elements without expensive DMA transfersabstractTraditionally, Instruction set extension (ISE) algorithms have treated memory and control flow as invalid operations during custom instruction identification to ensure deterministic latency of these extended instructions. In order to overcome these constraints some work has been done to incorporate local memory for custom instructions with memory operations. Such architectures have invariably relied on the expensive DMA protocol for data transfer. Cache-coherence management poses another challenge in such systems and requires additional hardware and/or software intervention. We propose a novel custom instruction architecture capable of incorporating certain types of memory and control-flow operations. Unlike existing architectures, the proposed design eliminates the need for expensive Direct Memory Access (DMA) transfers and additional cache management sub-systems, thereby saving significant time and energy. Our method is focused mainly on accelerating code segments with static variables as well as the ones allocated on the stack, which are widely prevalent in embedded applications. Experimental results show that the proposed method achieves a substantial performance gain of upto 47% over base processor implementation. Alok Prakash, Christopher T. Clarke, Thambipillai Srikanthan |
FPL | 1 |
| 2009 | Mapping Algorithms for NoC-Based Heterogeneous MPSoC PlatformsabstractMapping of applications onto multiprocessor system-on-chip (MPSoC) can be realized either at design-time or run-time. At any time the number of tasks executing in MPSoC platform can exceed the available resources, requiring efficient run-time mapping techniques to meet the real-time constraints of the applications. This paper presents two run-time mapping heuristics for mapping the tasks of an application in close proximity so as to minimize the communication overhead. In particular, the communication overhead between two adjacent hardware tasks is eliminated by mapping them onto the same reconfigurable processing node. We show that the proposed approach is capable of alleviating network-on-chip (NoC) congestion bottlenecks to optimize the overall performance. Based on our investigations to map the tasks of applications' at run-time onto an 8×8 NoC-based heterogeneous MPSoC, our mapping heuristics are capable of reducing total execution time and average channel load of applications when compared to state-of-the-art runtime mapping heuristics. Amit Kumar Singh 0002, Jigang Wu, Alok Prakash, Thambipillai Srikanthan |
DSD | 3 |
| 2009 | Rapid design exploration framework for application-aware customization of soft core processorsabstractOff-the-shelf soft core processors are becoming increasingly popular in embedded systems design today as they provide for application specific customization, in particular through instruction subsetting. However, choosing the right processor configuration remains a challenge as the search space becomes prohibitively large when the configurable options increase. In this paper we propose a framework to rapidly explore the processor configuration design space for a given application. Unlike existing approaches that require time-consuming synthesis process, the proposed method relies only on a single-pass output of the LLVM compiler infrastructure. Experimental results based on widely used benchmarks show that the proposed framework can reliably predict the actual performance and area trends of various configurable options. Alok Prakash, Siew-Kei Lam, Amit Kumar Singh 0002, Thambipillai Srikanthan |
FPL | 1 |