Junzhong Shen

Junzhong Shen


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 April 2019 in IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Verified
Journal Article
Closed access
JSJunzhong Shen
Junzhong Shen
YHYou Huang
You Huang
MWMei Wen
Mei Wen
CZChunyuan Zhang
Chunyuan Zhang
Three-dimensional convolutional neural networks (3D CNNs) are used efficiently in many computer vision applications. Most previous work in this area has concentrated only on design and optimization of accelerators for 2D CNNs, with few attempts having been made to accelerate 3D CNNs on FPGA. We find the acceleration of 3D CNNs on FPGA to be challenging due to their high computational complexity and storage demands. More importantly, although the computational patterns of 2D and 3D CNNs are analogous, the conventional approaches that have been adopted for acceleration of 2D CNNs may be unfit for 3D CNN acceleration. In this paper, in order to accelerate 2D and 3D CNNs using a uniform framework, we first propose a uniform template-based architecture that uses templates based on the Winograd algorithm to ensure the rapid development of 2D and 3D CNN accelerators. Then, with the aim of efficiently mapping all layers of 2D/3D CNNs onto a pipelined accelerator, techniques are developed to improve the throughput and computational efficiency of the accelerator, including layer fusion, layer clustering and workload-balancing scheme. Finally, we demonstrate the effectiveness of the deep pipelined architecture by accelerating real-life 2D and 3D CNNs on the state-of-the-art FPGA platform. On VCU118, we achieve 3.7 TOPS for VGG-16, which outperforms state-of-the-art FPGAbased CNN accelerators. Comparisons with CPU and GPU solutions demonstrate that our implementation of 3D CNN achieves gains of up to 17.8x and 64.2x in performance and energy relative to a CPU solution, and a 5.0x energy efficiency gain over a GPU solution.

30 January 2020 in IEEE Access
Verified
Journal Article
Open access
ZCZhuang Cao
Zhuang Cao
HSHuayou Su
Huayou Su
QYQianming Yang
Qianming Yang
JSJunzhong Shen
Junzhong Shen
MWMei Wen
Mei Wen
CZChunyuan Zhang
Chunyuan Zhang
This paper presents a framework for converting P4 programs to VHDL and then implementing them on Field-Programmable Gate Array (FPGA) platforms. In this framework, a match-action-based hardware architecture is introduced with clearly designed components, which correspond to the described functionalities in the P4 programs. A pre-built template library is used for the compilation that includes optimized VHDL templates corresponding to specific clearly designed components. From the output of a standard frontend P4 compiler, the proposed compiler extracts parameters and relationships within the functions being employed, maps them to corresponding templates by calling, configuring, optimizing and instantiating them, and finally generates the appropriate FPGA code. A pre-built evaluation library is also proposed that helps the compiler to optimize the implementation during the mapping phase. A prototype of this framework is also implemented and evaluated; in this process, it is found that the generated processors use few resources and have high throughput and low latency. Compared with a state-of-the-art solution, the packet processing time is halved. In addition, the generated processors are able to operate at a line rate of nearly 100 Gigabits per second for a basic layer-3 forwarding application.

18 July 2019 in Electronics
Verified
Journal Article
Open access
PDF file
DWDeguang Wang
Deguang Wang
JSJunzhong Shen
Junzhong Shen
MWMei Wen
Mei Wen
CZChunyuan Zhang
Chunyuan Zhang
Three-dimensional (3D) deconvolution is widely used in many computer vision applications. However, most previous works have only focused on accelerating two-dimensional (2D) deconvolutional neural networks (DCNNs) on Field-Programmable Gate Arrays (FPGAs), while the acceleration of 3D DCNNs has not been well studied in depth as they have higher computational complexity and sparsity than 2D DCNNs. In this paper, we focus on the acceleration of both 2D and 3D sparse DCNNs on FPGAs by proposing efficient schemes for mapping 2D and 3D sparse DCNNs on a uniform architecture. Firstly, a pruning method is used to prune unimportant network connections and increase the sparsity of weights. After being pruned, the number of parameters of DCNNs is reduced significantly without accuracy loss. Secondly, the remaining non-zero weights are encoded in coordinate (COO) format, reducing the memory demands of parameters. Finally, to demonstrate the effectiveness of our work, we implement our accelerator design on the Xilinx VC709 evaluation platform for four real-life 2D and 3D DCNNs. After the first two steps, the storage required of DCNNs is reduced up to 3.9×. Results show that the performance of our method on the accelerator outperforms that of the our prior work by 2.5× to 3.6× in latency.

1 July 2020
Verified
Conference Paper
Closed access
MTMinjin Tang
Minjin Tang
MWMei Wen
Mei Wen
JSJunzhong Shen
Junzhong Shen
XZXiaolei Zhao
Xiaolei Zhao
CZChunyuan Zhang
Chunyuan Zhang
Obtaining item frequencies in data streams with limited space is a well-recognized and challenging problem in a wide range of applications. Sketch-based solutions have been widely used to address this challenge due to their ability to accurately record the data streams at a low memory cost. However, most sketches suffer from low memory utilization due to the adoption of a fixed counter size. Accordingly, in this work, we propose a counter-cascading scheduling algorithm to maximize the memory utilization of sketches without incurring any accuracy loss. In addition, we propose an FPGA-based system design that supports sketch parameter learning, counter-cascading record and online query. We implement our designs on Xilinx VCU118, and conduct evaluations on real-world traces, thereby demonstrating that our design can achieve higher accuracy with lower storage; the performance achieved is 10× ∼ 20× better than that of state-of-the-art sketches.

16 January 2025 in IEEE Transactions on Very Large Scale Integration (VLSI) Systems
Verified
Journal Article
Closed access
HSHao Sun
Hao Sun
JSJunzhong Shen
Junzhong Shen
TZTian Zhang
Tian Zhang
ZTZhongyi Tang
Zhongyi Tang
CZChangwu Zhang
Changwu Zhang
HLHengzhu Liu
Hengzhu Liu
In recent years, deep neural networks (DNNs) have experienced rapid development. These DNNs demonstrate significant variations in architecture and scale, creating a substantial demand for domain-specific accelerators that are optimized for both high performance and low energy consumption. Systolic array accelerators, due to their efficient dataflow and parallel processing capabilities, offer significant advantages when performing computations for DNNs. Existing studies frequently overlook various hardware constraints in systolic array accelerators when representing mapping strategies. This oversight includes ignoring the differences in delays between communication and computation operations, as well as overlooking the capacities of multilevel memory hierarchies. Such omissions can lead to inaccuracies in predicting accelerator performance and inefficiencies in system design. We propose the FAMS framework, which introduces a memory-centric notation capable of fully representing the mapping of DNN operations on systolic array accelerators. Memory-centric notation moves away from the idealized assumptions of previous notations and considers various hardware constraints, thereby expanding the effective design and mapping spaces. The FAMS framework also includes a cycle-accurate simulator, which takes the hardware configurations, task descriptions, and mapping strategy represented by memory-centric notation as inputs, providing various metrics such as latency and energy consumption. The experimental results demonstrate that our proposed FAMS framework reduces latency by up to 29.7% and increases throughput by 42.4% compared to the state-of-the-art TENET framework. Additionally, under hardware configurations with a MAC delay of 2 and 3 clock cycles, the FAMS framework enhances performance by 12.0% and 25.4%, respectively.

26 July 2024 in IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Verified
Journal Article
Closed access
MTMinjin Tang
Minjin Tang
MWMei Wen
Mei Wen
JYJianchao Yang
Jianchao Yang
ZXZeyu Xue
Zeyu Xue
JSJunzhong Shen
Junzhong Shen
Sparse matrix-matrix multiplication (SpMM) and Generalized SpMM (SpGEMM) are essential computational kernels in domains, such as graph analytics and scientific computation. While systolic arrays have traditionally been employed as specialized architectures for complex computing problems like matrix multiplication, they exhibit inefficiency when dealing with sparse matrices. This inefficiency arises from the unnecessary operations performed by processing elements (PEs) that contain zero-valued entries, which do not contribute to the final result. To address this issue, we propose SPSA, a framework that leverages a sparse-packing algorithm suitable for systolic arrays to accelerate sparse matrix computations. Our approach achieves significant reduction of zero-valued items and improves matrix density by packing the rows or columns of the sparse matrix. Furthermore, we have introduced for the first time a data representation format tailored to systolic arrays, called CSXD, which further enhances storage and computational efficiency. Importantly, our adaptation scheme enables acceleration benefits even with limited resources. Through sparse packing, SPSA achieved a $5.2\times $ performance improvement compared to the dense baseline, and further reached a $6.4\times $ enhancement via CSXD. Simultaneously, CSXD realized an average storage efficiency improvement of $15.0\times $ . Through extensive evaluations, SPSA outperforms previous designs on CPU, GPU, and ASIC platforms. Finally, in end-to-end evaluations, SPSA achieved a performance improvement of 3.9 times across the workloads of BERT, VGG19, and ResNet50.