Zhiquan Lai

Prof. Zhiquan Lai


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

View All Publications
22 February 2023 in IEEE Transactions on Parallel and Distributed Systems
Verified
Journal Article
Closed access
ZLZhiquan Lai
Zhiquan Lai
SLShengwei Li
Shengwei Li
XTXudong Tang
Xudong Tang
KGKeshi Ge
Keshi Ge
WLWeijie Liu
Weijie Liu
DLDongsheng Li
Dongsheng Li
Foundation models are in the process of becoming the dominant deep learning technology. Pretraining a foundation model is always time-consuming due to the large scale of both the model parameter and training dataset. Besides being computing-intensive, the pretraining process is extremely memory- and communication-intensive. These challenges make it necessary to apply 3D parallelism, which integrates data parallelism, pipeline model parallelism, and tensor model parallelism, to achieve high training efficiency. However, current 3D parallelism frameworks still encounter two issues: i) they are not transparent to model developers, requiring manual model modification to parallelize training, and ii) their utilization of computation resources, GPU memory, and network bandwidth is insufficient. We propose Merak , an automated 3D parallelism deep learning training framework with high resource utilization. Merak automatically deploys 3D parallelism with an automatic model partitioner, which includes a graph-sharding algorithm and proxy node-based model graph. Merak also offers a non-intrusive API to scale out foundation model training with minimal code modification. In addition, we design a high-performance 3D parallel runtime engine that employs several techniques to exploit available training resources, including a shifted critical path pipeline schedule that increases computation utilization, stage-aware recomputation that makes use of idle worker memory, and sub-pipelined tensor model parallelism that overlaps communication and computation. Experiments on 64 GPUs demonstrate Merak's capability to speed up training performance over state-of-the-art 3D parallelism frameworks of models with 1.5, 2.5, 8.3, and 20 billion parameters by up to 1.42, 1.39, 1.43, and 1.61×, respectively.

26 June 2023 in IEEE Transactions on Parallel and Distributed Systems
Verified
Journal Article
Closed access
PLPeng Liang
Peng Liang
YTYu Tang
Yu Tang
XZXiaoda Zhang
Xiaoda Zhang
YBYouhui Bai
Youhui Bai
TSTeng Su
Teng Su
DLDongsheng Li
Dongsheng Li
Deep learning (DL) has gained great success in recent years, leading to state-of-the-art performance in research community and industrial fields like computer vision and natural language processing. One of the reasons for this success is the huge amount parameters adopted in DL models. However, it is impractical to train a moderately large model with a large number of parameters on a typical single device. Thus, It is necessary to train DL models in clusters with distributed training algorithms. However, traditional distributed training algorithms are usually sub-optimal and highly customized, which owns the drawbacks to train large-scale DL models in varying computing clusters. To handle the above problem, researchers propose auto-parallelism, which is promising to train large-scale DL models efficiently and practically in various computing clusters. In this survey, we perform a broad and thorough investigation on challenges, basis, and strategy searching methods of auto-parallelism in DL training. First, we abstract basic parallelism schemes with their communication cost and memory consumption in DL training. Further, we analyze and compare a series of current auto-parallelism works and investigate strategies and searching methods which are commonly used in practice. At last, we discuss several trends in auto-parallelism which are promising in further research.

28 May 2024 in IEEE Transactions on Parallel and Distributed Systems
Verified
Journal Article
Closed access
SLShengwei Li
Shengwei Li
KLKai Lu
Kai Lu
ZLZhiquan Lai
Zhiquan Lai
WLWeijie Liu
Weijie Liu
KGKeshi Ge
Keshi Ge
DLDongsheng Li
Dongsheng Li
The transformer-based deep neural network (DNN) models have shown considerable success across diverse tasks, prompting widespread adoption of distributed training methods such as data parallelism and pipeline parallelism. With the increasing parameter number, hybrid parallel training becomes imperative to scale training. The primary bottleneck in scaling remains the communication overhead. The communication scheduling technique, emphasizing the overlap of communication with computation, has demonstrated its benefits in scaling. However, most existing works focus on data parallelism, overlooking the nuances of hybrid parallel training. In this paper, we propose TriRace , an efficient communication scheduling framework for accelerating communications in hybrid parallel training of asynchronous pipeline parallelism and data parallelism. To achieve effective computation-communication overlap, TriRace introduces 3D communication scheduling , which adeptly leverages data dependencies between communication and computations, efficiently scheduling AllReduce communication, sparse communication, and peer-to-peer communication in hybrid parallel training. To avoid possible communication contentions, TriRace also incorporates a topology-aware runtime which optimizes the execution of communication operations by considering ongoing communication operations and real-time network status. We have implemented a prototype of TriRace based on PyTorch and Pipedream-2BW, and conducted comprehensive evaluations with three representative baselines. Experimental results show that TriRace achieves up to 1.07–1.45× speedup compared to the state-of-the-art pipeline parallelism training baseline Pipedream-2BW, and 1.24–1.81× speedup compared to the Megatron.

14 August 2023 in IEEE Transactions on Computers
Verified
Journal Article
Closed access
LZLizhi Zhang
Lizhi Zhang
KLKai Lu
Kai Lu
ZLZhiquan Lai
Zhiquan Lai
YFYongquan Fu
Yongquan Fu
YTYu Tang
Yu Tang
DLDongsheng Li
Dongsheng Li
Graph neural networks (GNNs) have been successfully applied to many important application domains on graph data. As graphs become increasingly large, existing GNN training frameworks typically use mini-batch sampling during feature aggregation to lower resource burdens, which unfortunately suffer from long memory accessing latency and inefficient data transfer of vertex features from CPU to GPU. This paper proposes 2PGraph, a system that addresses these limitations of mini-batch sampling and feature aggregation and supports fast and efficient single-GPU and distributed GNN training. First, 2PGraph presents a locality awareness GNN-training scheduling method that schedules the vertices based on the locality of the graph topology, significantly accelerating the sampling and aggregation, improving the data locality of vertex access, and limiting the range of neighborhood expansion. Second, 2PGraph proposes a GNN-layer-aware feature caching method on available GPU resources with a hit rate up to 100%, which avoids redundant data transfer between CPU and GPU. Third, 2PGraph presents a self-dependence cluster-based graph partition method, achieving high sampling and cache efficiency for distributed environments. Experimental results on real-world graph datasets show that 2PGraph reduces memory access latency by up to 90% mini-batch sampling, and data transfer time by up to 99%. For distributed GNN training over an 8-GPU cluster, 2PGraph achieves up to 8.7× performance speedup over state-of-the-art approaches.

5 April 2015 in The Journal of Supercomputing
Verified
Journal Article
Closed access
PDF file
ZLZhiquan Lai
Zhiquan Lai
KLKing Tin Lam
King Tin Lam
CWCho-Li Wang
Cho-Li Wang
JSJinshu Su
Jinshu Su

1 July 2019
Verified
Conference Paper
Closed access
DLDongsheng Li
Dongsheng Li
ZLZhiquan Lai
Zhiquan Lai
KGKeshi Ge
Keshi Ge
YZYiming Zhang
Yiming Zhang
ZZZhaoning Zhang
Zhaoning Zhang
HWHuaimin Wang
Huaimin Wang
With growing scale of the data volume and neural network size, we have come into the era of distributed deep learning. High-performance training and inference on distributed computing systems has been attracting increasing research attention in both academia and industry. Meanwhile, diversity of existing machine learning frameworks (e.g. TensorFlow, Pytorch and MXNet) and the explosion of deep learning hardwares (e.g. CPUs, GPUs, FPGAs and ASICs) bring more challenges for users to leverage new deep learning technologies and accelerating capability of hardware devices. We firstly search around the state-of-the-art work in the area which open our mind to take a vision upon the future deep learning framework. Then, we propose HPDL, a general framework for high-performance distributed deep learning which is compatible with existing frameworks and adaptive to various hardware architectures. At last, we discuss and foresee the key technologies fulfilling high-performance and large-scale deep learning, including optimization algorithm, hybrid communication mechanism, model parallelization, resource scheduling and single-node execution optimization.