VLDB 2026 Research / reviewers in the wild / expert
Pouya Haghi
dblp:268/1501
· DBLP profile ↗
17ranked-venue papers
6as first author
14since 2021 · last 2025
0000-0003-2893-9194ORCID · verified
Domains — the database's venue-derived domains; a paper can count in several
Systems, architecture and hardware · 16 · 6 first-author · 13 since 2021Artificial intelligence and machine learning · 1 · 1 since 2021Software engineering, systems software and programming languages · 1 · 1 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | DM-Tune: Quantizing Diffusion Models with Mixture-of-Gaussian Guided Noise TuningabstractDiffusion models have become essential generative tools for tasks such as image generation, video creation, and inpainting, but their high computational and memory demands pose challenges for efficient deployment. Contrary to the traditional belief that full-precision computation ensures optimal image quality, we demonstrate that a fine-grained mixed-precision strategy can surpass full-precision models in terms of image quality, diversity, and text-to-image alignment. However, directly implementing such strategies can lead to increased complexity and reduced runtime performance due to the overheads of managing multiple precision formats and casting operations. To address this, we introduce DM-Tune, which replaces complex mixed-precision quantization with a unified low-precision format, supplemented by noise-tuning, to improve both image generation quality and runtime efficiency. The proposed noise-tuning mechanism is a type of fine-tuning that reconstructs the mixed-precision output by learning adjustable noise through a parameterized nonlinear function consisting of Gaussian and linear components. Key steps in our framework include identifying sensitive layers for quantization, modeling quantization noise, and optimizing runtime with custom low-precision GPU kernels that support efficient noise-tuning. Experimental results across various diffusion models and datasets demonstrate that DM-Tune not only significantly improves runtime but also enhances diversity, quality, and text-to-image alignment compared to FP32, FP8, and state-of-the-art mixed-precision methods. Our approach is broadly applicable and lays a solid foundation for simplifying complex mixed-precision strategies at minimal cost. Pouya Haghi, Ali Falahati, Zahra Azad, Chunshu Wu, Ruibing Song, Chuan Liu 0001, Ang Li 0006, Tong Geng |
DAC | 1 |
| 2025 | InstaTrain: Adaptive Training via Ultra-Fast Natural Annealing within Dynamical SystemsabstractTime-series modeling is broadly adopted to capture underlying patterns present in historical data, allowing prediction of future values. However, one crucial aspect of such modeling is often overlooked: in highly dynamic environments, data distributions can shift drastically within a second or less. Under these circumstances, traditional predictive models, and even online learning methods, struggle to adapt to the ultra-fast and complex distribution shifts present in highly dynamic scenarios. To address this, we propose InstaTrain, a novel learning approach that enables ultra-fast model updates for real-world prediction tasks, thereby keeping pace with rapidly evolving data distributions. In this work, (1) we transform the slow and expensive training process into an ultra-fast natural annealing process within a dynamical system. (2) Leveraging a recently proposed electronic dynamical system, we augment the system with parameter update modules, extending its capabilities to encompass both rapid training and inference. Experimental results on highly dynamic datasets demonstrate that our method achieves orders-of-magnitude improvements in training speed and energy efficiency while delivering superior accuracy compared to baselines running on GPUs. Chuan Liu 0001, Ruibing Song, Chunshu Wu, Pouya Haghi, Tong Geng |
ICLR | 4 |
| 2025 | DS-TPU: Dynamical System for on-Device Lifelong Graph Learning with Nonlinear Node InteractionabstractGraph learning on dynamical systems has recently surfaced as an emerging research domain.By leveraging a novel electronic Dynamical System (DS), various graph learning challenges have been effectively tackled through a rapid, spontaneous natural annealing process.This method has attracted increasing attention due to its orders-of-magnitude improvements in speed and energy efficiency compared to traditional Graph Neural Network (GNN) approaches for inference tasks.However, (1) the current DS hardware only supports inference, missing its native solution for training; while relying on conventional hardware is likely more expensive than GNNs.(2) The current DS architecture only allows linear interactions among its nodes, limiting training accuracy.In this work, we present a Dynamical-System Training-Processing Unit (DS-TPU) developed through algorithm-architecture co-design to tackle the two major challenges: (1) An on-device lifelong learning mechanism that leverages feedback electric current as the loss function in response to the observed training data, allowing electron-speed refinement on the present model parameters.(2) A nonlinear DS node interaction mechanism constructed from Chebyshev polynomials to significantly improve the compatibility between the DS hardware and the embedded relation of graph data.Extensive evaluations using six real-world graph learning applications demonstrate that for accuracy, DS-TPU achieves 10.8% MAE reduction over the best results of five widely used GNNs.In terms of training performance, the 5-Watt DS-TPU architecture achieves onaverage 810× speedup over the offline training for DS on an Nvidia A100 GPU, and 640× over GNN training on the same GPU.In terms Chunshu Wu, Ruibing Song, Chuan Liu 0001, Pouya Haghi, Ang Li 0006, Tong Geng |
ISCA | 4 |
| 2024 | SmartFuse: Reconfigurable Smart Switches to Accelerate Fused Collectives in HPC ApplicationsabstractCommunication switches have sometimes been augmented to process collectives, e.g., in the IBM BlueGene and Mellanox SHArP switches. In this work, we find that there is a great acceleration opportunity through the further augmentation of switches to accelerate more complex functions that combine communication with computation. We consider three types of such functions. The first is fully-fused collectives built by fusing multiple existing collectives like Allreduce with Alltoall. The second is semi-fused collectives built by combining a collective with another computation. The third are higher-order collectives built by combining multiple computations and communications, such as to perform matrix-matrix multiply (PGEMM). Pouya Haghi, Cheng Tan 0002, Anqi Guo, Chunshu Wu, Dongfang Liu, Ang Li 0006, Anthony Skjellum, Tong Geng, Martin C. Herbordt |
ICS | 1 |
| 2024 | Bridging the Gap Between LLMs and LNS with Dynamic Data Format and Architecture CodesignabstractDeep Neural Networks (DNNs) have achieved tremendous success in the past few years. However, their training and inference demand exceptional computational and memory resources. Quantization has been shown as an effective approach to mitigate the cost, with the mainstream data types reduced from FP32 to FP16/BF16 and recently FP4 in the latest NVIDIA B100 GPUs. With increasingly aggressive quantization, however, the conventional floating-point formats suffer from limited precision in representing numbers around zero. Recently, NVIDIA demonstrated the potential of using a Logarithmic Number System (LNS) for the next generation of tensor cores. While LNS mitigates the hurdles in representing small numbers, in this work we observed a mismatch between LNS and the emerging Large Language Models (LLM), where LLM exhibits significant outliers when directly adopting the LNS format. In this paper, we present a data-format/architecture codesign to bright this gap. On the format side, we propose a dynamic LNS format to flexibly represent outliers at a higher precision, by exploiting asymmetry in the LNS representation and identifying outliers through a per-block basis. On the architecture side, for demonstration, we realize the dynamic LNS format in a systolic array, which can handle the irregularity of the outliers at runtime. We implement our approach on an Alveo U280 FPGA as a prototype. Experimental results show that our design can effectively handle the outliers and resolve the mismatch between LNS and LLM, contributing to an accuracy improvement of 15.4% and 16% over the floating-point and the original LNS baselines, with up to 15.3% over the state-of-the-art quantization methods using four LLM models. Our observation and design lay a solid foundation for the large-scale adoption of the LNS format in the next-generation deep learning hardware. Pouya Haghi, Chunshu Wu, Zahra Azad, Andrew Gui, Yuchen Hao, Ang Li 0006, Tong Geng |
MICRO | 1 |
| 2024 | FPGA-Accelerated Range-Limited Molecular DynamicsabstractLong timescale Molecular Dynamics (MD) simulation of small molecules is crucial in drug design and basic science. To accelerate a small data set that is executed for a large number of iterations, high-efficiency is required. Recent work in this domain has demonstrated that among COTS devices only FPGA-centric clusters can scale beyond a few processors. The problem addressed here is that, as the number of on-chip processors has increased from fewer than 10 into the hundreds, previous intra-chip routing solutions are no longer viable. We find, however, that through various design innovations, high efficiency can be maintained. These include replacing the previous broadcast networks with ring-routing and then augmenting the rings with out-of-order and caching mechanisms. Others are adding a level of hierarchical filtering and memory recycling. Two novel optimized architectures emerge, together with a number of variations. These are validated, analyzed, and evaluated. We find that in the domain of interest speed-ups over GPUs are achieved. The potential impact is that this system promises to be the basis for scalable long timescale MD with commodity clusters. Chunshu Wu, Chen Yang 0010, Sahan Bandara, Tong Geng, Anqi Guo, Pouya Haghi, Ang Li 0006, Martin C. Herbordt |
IEEE Trans. Computers | 6 |
| 2023 | Software-Hardware Co-design of Heterogeneous SmartNIC System for Recommendation Models Inference and TrainingabstractDeep Learning Recommendation Models (DLRMs) are important applications in various domains and have evolved into one of the largest and most important machine learning applications. With their trillions of parameters necessarily exceeding the high bandwidth memory (HBM) capacity of GPUs, ever more massive DLRMs require large-scale multi-node systems for distributed training and inference. However, these all suffer from the all-to-all communication bottleneck, which limits scalability. Anqi Guo, Yuchen Hao, Chunshu Wu, Pouya Haghi, Zhenyu Pan, Min Si, Dingwen Tao, Ang Li 0006, Martin C. Herbordt, Tong Geng |
ICS | 4 |
| 2023 | FLASH: FPGA-Accelerated Smart Switches with GCN Case StudyabstractSome communication switches, e.g., the Mellanox SHArP and those in the IBM BlueGene clusters, are augmented to process packets at the application level with fixed-function collectives. This approach, however, lacks flexibility, which limits their applicability in diverse and dynamic workloads. Recently, a new type of programmable packet processor, which uses high-level languages, e.g., P4, has emerged as a possible candidate. P4-based switches, however, fall short in certain applications, including machine learning, where capabilities not currently supported by P4 are needed. These include more complex calculation, such as sparse computation and fused multiply-accumulate, data-intensive floating point operations, data reuse, and significant memory. The problem addressed here is that such a switch augmentation needs to support: a large amount of state, significant flexible compute capability, and ease of programming, all while maintaining full functionality, including ensuring high throughput, and demonstrating utility. Pouya Haghi, William Krska, Cheng Tan 0002, Tong Geng, Po-Hao Chen 0002, Connor Greenwood, Anqi Guo, Thomas M. Hines, Chunshu Wu, Ang Li 0006, Anthony Skjellum, Martin C. Herbordt |
ICS | 1 |
| 2023 | FASDA: An FPGA-Aided, Scalable and Distributed Accelerator for Range-Limited Molecular DynamicsabstractConducting long-timescale simulations of small molecules using Molecular Dynamics (MD) is crucial in drug design. However, traditional methods to accelerate the process, including ASICs or GPUs, have limitations. ASIC solutions are not always generally available, while GPU solutions may not scale when processing small molecules. FPGAs are both communication processors and accelerators, with tight coupling between these capabilities, and so could be used to address strong scaling in this domain. Chunshu Wu, Tong Geng, Anqi Guo, Sahan Bandara, Pouya Haghi, Chuan Liu 0001, Ang Li 0006, Martin C. Herbordt |
SC | 5 |
| 2022 | FCsN: A FPGA-Centric SmartNIC Framework for Neural NetworksabstractNetwork communication is increasingly becoming the performance bottleneck for scaled-out HPC and warehouse applications, as enormous CPU processing is devoted to packet processing, contributing to long latencies. To reduce this latency, advanced network interface cards known as SmartNICs have been introduced to handle networking functions. Dozens of commercial FPGA-based SmartNICs have been released (e.g., [1] – [3] and see surveys [4] , [5] ). Other commercial SmartNICs have been developed also with the aim of near-network processing [6] – [9] . There is also prior art that uses SmartNICs as compute resources [10] , [11] . For instance, COPA [12] , INCA [13] , sPIN [14] provide a portable programming model to offload simple packet processing. Other work (e.g., [15] – [21] ) supports collectives in FPGA-based hardware. Anqi Guo, Tong Geng, Yongan Zhang, Pouya Haghi, Chunshu Wu, Cheng Tan 0002, Yingyan (Celine) Lin, Ang Li 0006, Martin C. Herbordt |
FCCM | 4 |
| 2022 | COPA Use Case: Distributed Secure Joint ComputationabstractData centers provide good environments for distributed computing as they are easily accessible and may have low-latency communication between nodes [1] ; often, however, performance is limited by network bandwidth. These network bottlenecks drive the need for alternative communication resources to improve performance of large-scale applications. SmartNICs [2] – [4] have been introduced to perform the same tasks of standard NICs, but contain additional resources to allow for network function optimization with additional hardware. Adoption of SmartNICs continues to increase as a means to accelerate network functions and offload packet processing tasks away from CPU resources [5] – [13] . Rushi Patel, Pouya Haghi, Shweta Jain 0005, Andriy Kot, Venkata Krishnan, Mayank Varia, Martin C. Herbordt |
FCCM | 2 |
| 2022 | A Framework for Neural Network Inference on FPGA-Centric SmartNICsabstractFPGA-based SmartNICs offer great potential to significantly improve the performance of high-performance computing and warehouse data processing by tightly coupling support for reconfigurable data-intensive computation with cross-node communication thereby mitigating the von Neumann bottleneck. Existing work however has generally been limited in that it assumes an accelerator model where kernels are offloaded to SmartNICs with most control tasks left to the CPUs. This leads to frequent waiting reduced performance and scaling challenges. In this work we propose a new distributive data-centric computing framework named FCsN for reconfigurable SmartNIC-based systems. Through a lightweight task circulation execution model and its implementation architecture FCsN allows the complete detaching of NN kernel execution control logic system scheduling and network communication to the SmartNICs. This boosts performance by (i) avoiding control dependency with CPUs and (ii) supporting streaming NN kernel execution and network communication at line rate and in a very fine-grained manner. We demonstrate the efficiency and flexibility of FCsN using various types of neural network kernels and applications including deep neural networks (DNN) and graph neural networks (GNN) as these last are both irregular and data intensive they offer an especially robust demonstration. Evaluations using commonly-used neural network models and graph datasets show that a system with FCsN can achieve 10 × speedups over the MPI-based standard CPU baselines Anqi Guo, Tong Geng, Yongan Zhang, Pouya Haghi, Chunshu Wu, Cheng Tan 0002, Yingyan (Celine) Lin, Ang Li 0006, Martin C. Herbordt |
FPL | 4 |
| 2022 | Optimized Mappings for Symmetric Range-Limited Molecular Force Calculations on FPGAsabstractIn N-body applications, the efficient evaluation of range-limited forces depends on applying certain constraints, including a cut-off radius and force symmetry (Newton's Third Law). When computing the pair-wise forces in parallel, finding the optimal mapping of particles and computations to memories and processors is surprisingly challenging, but can result in greatly reduced data movement and computation. Despite FPGAs having a distinct compute model (BRAMs/network/pipelines) from CPUs and ASICs, mappings on FPGAs have not previously been studied in depth: it was thought that the half-shell method was preferred. In this work, we find that the Manhattan method is sur-prisingly compatible with FPGA hardware. With the cache overlapping technique proposed in this paper, the ultra-fine-grained data access demanded by the Manhattan method can be satisfied, despite the fact that the memory blocks on FPGAs appear to be insufficiently fine-grained. We further demonstrate that, compared to the traditional baseline half-shell method, approximately a half of the filters (preprocessors) can be removed without performance degradation. For communication, the amount of data transferred can be reduced by 40% - 75% in the most common multi-FPGA scenarios. Moreover, data transfers are almost perfectly balanced along all directions, and the optimization requires only minimal hardware resources. The practical consequence is that nearly 2 x to 4 x the workload can be handled without upgrading the network connections between FPGAs. This is a critical finding given the relatively limited bandwidth available in many common accelerator boards and the strong-scaling applications to which FPGA clusters are being applied. Chunshu Wu, Sahan Bandara, Tong Geng, Anqi Guo, Pouya Haghi, Vipin Sachdeva, Woody Sherman, Martin C. Herbordt |
FPL | 5 |
| 2022 | Reconfigurable switches for high performance and flexible MPI collectivesabstractAbstract There has been much effort in offloading MPI collective operations into hardware. But while NIC‐based collective acceleration is well‐studied, offloading their processing into the switching fabric, despite numerous advantages, has been much more limited. A major problem with fixed logic implementations is that either only a fraction of the possible collective communication is accelerated or that logic is wasted in the applications that do not need a particular capability. Using reconfigurable logic has numerous advantages: exactly the required operations can be implemented; the level of desired performance can be specified; and new, possibly complex, operations can be defined and implemented. We have designed an in‐switch collective accelerator,MPI‐FPGA, and demonstrated its use with seven MPI collectives and over a set of benchmarks and proxy applications (MiniApps). The accelerator uses a novel two‐level switch design containing fully pipelined vectorized aggregation logic units. Essential to this work is providing support for sub‐communicator collectives that enables communicators of arbitrary shape, and that is scalable to large systems. A streaming interface improves the performance for long messages. While this reconfigurable design is generally applicable, we prototype it with an FPGA‐centric cluster. A sampleMPI‐FPGAdesign in a direct network achieves considerable speedups over conventional clusters in the most likely scenarios. We also present results for indirect networks with reconfigurable high‐radix switches and show that this approach is competitive withSHArPtechnology for the subset of operations thatSHArPsupports.MPI‐FPGAis fully integrated into MPICH and is transparent to MPI applications. Pouya Haghi, Anqi Guo, Qingqing Xiong, Chen Yang 0010, Tong Geng, Justin T. Broaddus, Ryan J. Marshall, Derek Schafer, Anthony Skjellum, Martin C. Herbordt |
Concurr. Comput. Pract. Exp. | 1 |
| 2020 | FP-AMG: FPGA-Based Acceleration Framework for Algebraic Multigrid SolversabstractPartial Differential Equations (PDEs) are fundamental to many real-world scientific computing applications and so their optimization has undergone decades of study. Algebraic multigrid (AMG) is one of the most well-known solvers, being widely adopted in High Performance Computing (HPC) due to its good scalability. Acceleration of AMG is known to be very challenging, due to the following reasons: (1) irregular computation patterns, (2) random memory access, and (3) a large number of kernels with various computation types. To the best of our knowledge, there is no prior work on FPGA-based acceleration of AMG. To tackle these challenges, we propose an efficient FPGA-based reconfigurable framework, called FP-AMG, for high-performance AMG calculation. In order to obtain full pipeline utilization, we propose a novel and scalable architecture that can be reused for all kernels in AMG. Given that AMG is strictly memory-bound, we propose algorithmic and architectural optimizations to ensure nearly ideal use of memory bandwidth. The efficiency of FP-AMG is evaluated with six well-known benchmarks on two FPGA devices: one with and one without high bandwidth memory (HBM). The experimental results are compared with a highly optimized Intel Xeon E5-2680-V4 implementation of the state-of-the-art HYPRE library. Our experiments show that FP-AMG can achieve average speedups of $ 2.5\times$ and $ 6.6\times$, for FPGAs without and with HBM, respectively. Pouya Haghi, Tong Geng, Anqi Guo, Martin C. Herbordt |
FCCM | 1 |
| 2020 | Accelerating MPI Collectives with FPGAs in the Network and Novel Communicator SupportabstractMPI collective operations can often be performance killers in HPC applications; we seek to solve this bottleneck by offloading them to reconfigurable hardware within the switch itself, rather than, e.g., the NIC. We have designed a hardware accelerator MPI-FPGA to implement six MPI collectives in the network. Preliminary results show that MPI-FPGA achieves $10 \times $ speedup in the most likely scenarios over conventional clusters. We introduce a novel mechanism that enables the hardware to support a large number of communicators of arbitrary shape, and that is scalable to very large systems. MPI-FPGA is fully integrated into MPICH and so transparent to MPI applications. Qingqing Xiong, Chen Yang 0010, Pouya Haghi, Anthony Skjellum, Martin C. Herbordt |
FCCM | 3 |
| 2020 | AWB-GCN: A Graph Convolutional Network Accelerator with Runtime Workload RebalancingabstractDeep learning systems have been successfully applied to Euclidean data such as images, video, and audio. In many applications, however, information and their relationships are better expressed with graphs. Graph Convolutional Networks (GCNs) appear to be a promising approach to efficiently learn from graph data structures, having shown advantages in many critical applications. As with other deep learning modalities, hardware acceleration is critical. The challenge is that real-world graphs are often extremely large and unbalanced; this poses significant performance demands and design challenges. In this paper, we propose Autotuning-Workload-Balancing GCN (AWB-GCN) to accelerate GCN inference. To address the issue of workload imbalance in processing real-world graphs, three hardware-based autotuning techniques are proposed: dynamic distribution smoothing, remote switching, and row remapping. In particular, AWB-GCN continuously monitors the sparse graph pattern, dynamically adjusts the workload distribution among a large number of processing elements (up to 4K PEs), and, after converging, reuses the ideal configuration. Evaluation is performed using an Intel D5005 FPGA with five commonly-used datasets. Results show that 4K-PE AWB-GCN can significantly elevate PE utilization by 7.7× on average and demonstrate considerable performance speedups over CPUs (3255×), GPUs (80.3×), and a prior GCN accelerator (5.1×). Tong Geng, Ang Li 0006, Runbin Shi, Chunshu Wu, Pouya Haghi, Antonino Tumeo, Shuai Che, Steven K. Reinhardt, Martin C. Herbordt |
MICRO | 7 |