Hanhwi Jang

Research Interests

• Computer Architecture
• Performance Modeling & Analysis
• HW/SW Co-optimization for System Applications
• Operating System & Compiler

Work Experience

• Google LLC, Mountain View, USA.
  
  • Software Engineer
  • Feb. 2024 — Present


• Ajou University, Suwon, Korea.
  
  • Assistant Professor
  • Sep. 2020 — Feb. 2024


• Samsung Research, Seoul, Korea.
  
  • Staff Engineer, On-Device Lab
  • May 2019 — Aug. 2020

Education

• Pohang University of Science and Technology (POSTECH) , Pohang, Korea
  • Ph.D in the Dept. of Computer Science and Engineering
  • High Performance Computing Laboratory
  • Advisors: Prof. Jangwoo Kim and Prof. Jong Kim
  • Mar. 2012 — Feb. 2019


• Pohang University of Science and Technology (POSTECH) , Pohang, Korea
  • B.S. in the Dept. of Computer Science and Engineering
  • Summa cum laude, ranked first place in CSE dept.
  • Mar. 2008 — Feb. 2012

Publications

• IntervalSim++: Enhanced Interval Simulation for Unbalanced Processor Designs
  Haseung Bong, Nahyeon Kang, Youngsok Kim, Joonsung Kim, Hanhwi Jang
  IEEE Computer Architecture Letters, 2024


• GCStack: A GPU Cycle Accounting Mechanism for Providing Accurate Insight into GPU Performance
  Hanna Cha, Sungchul Lee, Yeonan Ha, Hanhwi Jang, Joonsung Kim, Youngsok Kim
  IEEE Computer Architecture Letters, 2024


• Fast, Light-weight, and Accurate Performance Evaluation using Representative Datacenter Behaviors
  Jaewon Lee, Dongmoon Min, Ilkwon Byun, *Hanhwi Jang, Jangwoo Kim * correspondence
  24th ACM/IFIP International Middleware Conference, Dec 2023


• Enabling Fine-Grained Spatial Multitasking on Systolic-Array NPUs Using Dataflow Mirroring
  Jinwoo Choi, Yeonan Ha, Jounghoo Lee, Sangsu Lee, Jinho Lee, Hanhwi Jang, Youngsok Kim
  IEEE Transactions on Computers, August 2023


• LSim: Fine-Grained Simulation Framework for Large-Scale Performance Evaluation
  Hamin Jang, Taehun Kang, Joonsung Kim, Jaeyong Cho, Jae-Eon Jo, Seungwook Lee, Wooseok Chang, Jangwoo Kim, Hanhwi Jang
  IEEE Computer Architecture Letters (CAL), April 2022


• GCoM: A Detailed GPU Core Model for Accurate Analytical Modeling of Modern GPUs
  Jounghoo Lee, Yeonan Ha, Suhyun Lee, Jinyoung Woo, Jinho Lee, Hanhwi Jang, and Youngsok Kim
  49th IEEE/ACM International Symposium on Computer Architecture (ISCA), June 2022


• The gem5 Simulator: Version 20.0+
  Jason Lowe Power and others I participated in this work with 77 co-authors
  arXiv:2007.03152, July 2020
  


• MnnFast: A Fast and Scalable System Architecture for Memory-Augmented Neural Networks
  *Hanhwi Jang, *Joonsung Kim, Jae-Eon Jo, Jaewon Lee, and Jangwoo Kim
  * both authors equally contributed to this work.
  The 46th International Symposium on Computer Architecture (ISCA), June 2019
  [Lightning Talk]


• RpStacks-MT: A High-Throughput Design Evaluation Methodology for Multi-Core Processors
  Hanhwi Jang, Jae-Eon Jo, Jaewon Lee, and Jangwoo Kim
  51th IEEE/ACM International Symposium on Microarchitecture (MICRO), Oct. 2018
  [Lightning Talk]


• DiagSim: Systematically Diagnosing Simulators for Healthy Simulations
  Jae-Eon Jo, Gyu-Hyeon Lee, Hanhwi Jang, Jaewon Lee, Mohammadamin Ajdari, and Jangwoo Kim
  ACM Transactions of Architecture and Code Optimization (TACO), 2018
  


• GPUpd: A Fast and Scalable Multi-GPU Architecture Using Cooperative Projection and Distribution
  Youngsok Kim, Jae-Eon Jo, Hanhwi Jang, Minsoo Rhu, Hanjun Kim, and Jangwoo Kim
  50th IEEE/ACM International Symposium on Microarchitecture (MICRO), Oct. 2017
  


• StressRight: Finding the Right Stress for Accurate In-development System Evaluation
  Jaewon Lee, Hanhwi Jang, Jae-eon Jo, Gyu-hyeon Lee, and Jangwoo Kim
  2017 IEEE International Symposium on Performance Analysis of Systems and Software (ISPASS)
  


• RpStacks: Fast and Accurate Processor Design Space Exploration Using Representative Stall-Event Stacks
  *Jaewon Lee, *Hanhwi Jang, and Jangwoo Kim
  * both authors equally contributed to this work.
  The 47th ACM/IEEE International Symposium on Microarchitecture (MICRO), Dec. 2014
  

Honors and Awards

• TJ PARK Graduate Fellowship, POSCO TJ Park Foundation
• Mar. 2012 — Feb. 2015


• National Science and Engineering Scholarship, Korea Student Aid Foundation
• Mar. 2008 — Feb. 2012


• Scholarship of Academic Achievment, POSTECH
  
  • Spring 2008 Semester
  • Fall 2008 Semester
  • Sprint 2009 Semester


• DEFCON Capture The Flag
  • DEFCON 19 CTF, 8th place (PLUS@Postech), Aug. 2011
  • DEFCON 18 CTF, 3rd place (KAIST@Postech), Aug. 2010

Teaching Experience

• Lecturer
• Spring 2022, ECE757 Parallel Computer Architecture, Ajou University
• Spring 2022, ECE358 Digial System Design, Ajou University
• Spring 2021, ECE755 Special Topics in Computers 1: Computer Architecture, Ajou University
• Fall 2020, ECE309 Operating System for EE, Ajou University
• Fall 2020, Fall 2021, ECE105 Data Analysis and Statistics, Ajou University


• Teaching Assistant
• Spring 2012, CSED311 Computer Architecture, POSTECH
• Fall 2013, CSED211 Microprocessor, POSTECH