Jinwoo Park

I am a computer science PhD candidate at INA lab, KAIST advised by Dongsu Han. Before then, I received my MS degree in Electrical Engineering at KAIST, advised by Yung Yi. Also, I have received BS degree in Electrical Engineering at KAIST.

My interests are in crafting computer systems that incorporate AI/ML approaches. I concentrate on integrating AI/ML techniques to the real-world systems for more efficient and better performance management policies. My works aims at 1) designing efficient system built on AI/ML approaches; 2) improving AI/ML approaches by exploiting system-specific assumptions. All my work involves several months of implementation followed by thorough testing in real-world data.

Recently, I am striving to develop an adaptive load control framework for microservices using AI/ML approaches. In the past, I worked on various topics including resource optimization in SLO-oriented microservices, optimizing image compression for accelerating neural restoration, and designing wireless MAC with a multi-agent RL approach.

Selected Publications

CVPR

AccelIR: Task-Aware Image Compression for Accelerating Neural Restoration

Juncheol Ye, Hyunho Yeo, Jinwoo Park, and Dongsu Han

Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 2023

Abs HTML

Recently, deep neural networks have been successfully applied for image restoration (IR)(eg, super-resolution, de-noising, de-blurring). Despite their promising performance, running IR networks requires heavy computation. A large body of work has been devoted to addressing this issue by designing novel neural networks or pruning their parameters. However, the common limitation is that while images are saved in a compressed format before being enhanced by IR, prior work does not consider the impact of compression on the IR quality. In this paper, we present AccelIR, a framework that optimizes image compression considering the end-to-end pipeline of IR tasks. AccelIR encodes an image through IR-aware compression that optimizes compression levels across image blocks within an image according to the impact on the IR quality. Then, it runs a lightweight IR network on the compressed image, effectively reducing IR computation, while maintaining the same IR quality and image size. Our extensive evaluation using seven IR networks shows that AccelIR can reduce the computing overhead of super-resolution, de-nosing, and de-blurring by 49%, 29%, and 32% on average, respectively.

CoNEXT

GRAF: A graph neural network based proactive resource allocation framework for SLO-oriented microservices

Jinwoo Park, Byungkwon Choi, Chunghan Lee, and Dongsu Han

Proceedings of the 17th International Conference on emerging Networking EXperiments and Technologies, 2021

Abs HTML

Microservice is an architectural style that has been widely adopted in various latency-sensitive applications. Similar to the monolith, autoscaling has attracted the attention of operators for managing resource utilization of microservices. However, it is still challenging to optimize resources in terms of latency service-level-objective (SLO) without human intervention. In this paper, we present GRAF, a graph neural network-based proactive resource allocation framework for minimizing total CPU resources while satisfying latency SLO. GRAF leverages front-end workload, distributed tracing data, and machine learning approaches to (a) observe/estimate impact of traffic change (b) find optimal resource combinations (c) make proactive resource allocation. Experiments using various open-source benchmarks demonstrate that GRAF successfully targets latency SLO while saving up to 19% of total CPU resources compared to the fine-tuned autoscaler. Moreover, GRAF handles traffic surge with 36% fewer resources while achieving up to 2.6x faster tail latency convergence compared to the Kubernetes autoscaler.

MobiHoc

Neuro-DCF: Design of wireless MAC via multi-agent reinforcement learning approach

Sangwoo Moon, Sumyeong Ahn, Kyunghwan Son, Jinwoo Park and Yung Yi

Proceedings of the Twenty-second International Symposium on Theory, Algorithmic Foundations, and Protocol Design for Mobile Networks and Mobile Computing, 2021

Abs HTML

The carrier sense multiple access (CSMA) algorithm has been used in the wireless medium access control (MAC) under standard 802.11 implementation due to its simplicity and generality. An extensive body of research on CSMA has long been made not only in the context of practical protocols, but also in a distributed way of optimal MAC scheduling. However, the current state-of-the-art CSMA (or its extensions) still suffers from poor performance, especially in multi-hop scenarios, and often requires patch-based solutions rather than a universal solution. In this paper, we propose an algorithm which adopts an experience-driven approach and train CSMA-based wireless MAC by using deep reinforcement learning. We name our protocol, Neuro-DCF. Two key challenges are: (i) a stable training method for distributed execution and (ii) a unified training method for embracing various interference patterns and configurations. For (i), we adopt a multi-agent reinforcement learning framework, and for (ii) we introduce a novel graph neural network (GNN) based training structure. We provide extensive simulation results which demonstrate that our protocol, Neuro-DCF, significantly outperforms 802.11 DCF and O-DCF, a recent theory-based MAC protocol, especially in terms of improving delay performance while preserving optimal utility. We believe our multi-agent reinforcement learning based approach would get broad interest from other learning-based network controllers in different layers that require distributed operation.
Publications
1. HotStorage
  
  SAND: A Storage Abstraction for Video-based Deep Learning
  
  Uitaek Hong, Hwijoon Lim, Hyunho Yeo, Jinwoo, Park, Dongsu Han
  
  15th ACM Workshop on Hot Topics in Storage and File Systems, 2023
  
  Abs HTML
  
  To Appear.
  
  CVPR
  
  AccelIR: Task-Aware Image Compression for Accelerating Neural Restoration
  
  Juncheol Ye, Hyunho Yeo Jinwoo, Park, and Dongsu Han
  
  Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 2023
  
  ABS HTML
  
  Recently, deep neural networks have been successfully applied for image restoration (IR)(eg, super-resolution, de-noising, de-blurring). Despite their promising performance, running IR networks requires heavy computation. A large body of work has been devoted to addressing this issue by designing novel neural networks or pruning their parameters. However, the common limitation is that while images are saved in a compressed format before being enhanced by IR, prior work does not consider the impact of compression on the IR quality. In this paper, we present AccelIR, a framework that optimizes image compression considering the end-to-end pipeline of IR tasks. AccelIR encodes an image through IR-aware compression that optimizes compression levels across image blocks within an image according to the impact on the IR quality. Then, it runs a lightweight IR network on the compressed image, effectively reducing IR computation, while maintaining the same IR quality and image size. Our extensive evaluation using seven IR networks shows that AccelIR can reduce the computing overhead of super-resolution, de-nosing, and de-blurring by 49%, 29%, and 32% on average, respectively.
  
  CoNEXT
  
  GRAF: A graph neural network based proactive resource allocation framework for SLO-oriented microservices
  
  Jinwoo Park, Byungkwon Choi, Chunghan Lee, and Dongsu Han
  
  Proceedings of the 17th International Conference on emerging Networking EXperiments and Technologies, 2021
  
  Abs HTML
  
  Microservice is an architectural style that has been widely adopted in various latency-sensitive applications. Similar to the monolith, autoscaling has attracted the attention of operators for managing resource utilization of microservices. However, it is still challenging to optimize resources in terms of latency service-level-objective (SLO) without human intervention. In this paper, we present GRAF, a graph neural network-based proactive resource allocation framework for minimizing total CPU resources while satisfying latency SLO. GRAF leverages front-end workload, distributed tracing data, and machine learning approaches to (a) observe/estimate impact of traffic change (b) find optimal resource combinations (c) make proactive resource allocation. Experiments using various open-source benchmarks demonstrate that GRAF successfully targets latency SLO while saving up to 19% of total CPU resources compared to the fine-tuned autoscaler. Moreover, GRAF handles traffic surge with 36% fewer resources while achieving up to 2.6x faster tail latency convergence compared to the Kubernetes autoscaler.
  
  MobiHoc
  
  Neuro-DCF: Design of wireless MAC via multi-agent reinforcement learning approach
  
  Sangwoo Moon, Sumyeong Ahn, Kyunghwan Son, Jinwoo Park, and Yung Yi
  
  Proceedings of the Twenty-second International Symposium on Theory, Algorithmic Foundations, and Protocol Design for Mobile Networks and Mobile Computing, 2021
  
  Abs HTML
  
  The carrier sense multiple access (CSMA) algorithm has been used in the wireless medium access control (MAC) under standard 802.11 implementation due to its simplicity and generality. An extensive body of research on CSMA has long been made not only in the context of practical protocols, but also in a distributed way of optimal MAC scheduling. However, the current state-of-the-art CSMA (or its extensions) still suffers from poor performance, especially in multi-hop scenarios, and often requires patch-based solutions rather than a universal solution. In this paper, we propose an algorithm which adopts an experience-driven approach and train CSMA-based wireless MAC by using deep reinforcement learning. We name our protocol, Neuro-DCF. Two key challenges are: (i) a stable training method for distributed execution and (ii) a unified training method for embracing various interference patterns and configurations. For (i), we adopt a multi-agent reinforcement learning framework, and for (ii) we introduce a novel graph neural network (GNN) based training structure. We provide extensive simulation results which demonstrate that our protocol, Neuro-DCF, significantly outperforms 802.11 DCF and O-DCF, a recent theory-based MAC protocol, especially in terms of improving delay performance while preserving optimal utility. We believe our multi-agent reinforcement learning based approach would get broad interest from other learning-based network controllers in different layers that require distributed operation.
  
  APNet
  
  pHPA: A proactive autoscaling framework for microservice chain
  
  Byungkwon Choi, Jinwoo Park, Chunghan Lee, and Dongsu Han
  
  5th Asia-Pacific Workshop on Networking, 2021
  
  Abs HTML
  
  Microservice is an architectural style that breaks down monolithic applications into smaller microservices and has been widely adopted by a variety of enterprises. Like the monolith, autoscaling has attracted the attention of operators in scaling microservices. However, most existing approaches of autoscaling do not consider microservice chain and severely degrade the performance of microservices when traffic surges. In this paper, we present pHPA, an autoscaling framework for the microservice chain. pHPA proactively allocates resources to the microservice chains and effectively handles traffic surges. Our evaluation using various open-source benchmarks shows that pHPA reduces 99%-tile latency and resource usage by up to 70% and 58% respectively compared to the most widely used autoscaler when traffic surges.