Page 75 - profile2014.indd

助研究員
張原豪 Yuan-Hao Chang

Assistant Research Fellow
Ph.D., Computer Science and Information Engineering,
National Taiwan University
Tel: 886-2-2788-3799 ext. 1612 Fax: 886-2-2782-4814
Email: johnson@iis.sinica.edu.tw http://www.iis.sinica.edu.tw/pages/johnson

Research Description ● Best paper nomination at the
ACM/IEEE Design Automation
My research interests lie in the area of computer systems, with an emphasis on storage systems Conference (DAC) (2014, 2007)
and embedded systems. ● Master Thesis Supervision Award,
Institute of Information and
One of my recent projects focuses on storage system designs for embedded systems. Embedded Computing Machinery (IICM).
systems, especially battery-powered consumer electronics such as smartphones, usually adopt (2013, 2011)
ash memory as their storage medium. Because of their reduced cost and advances in manufac-

turing technologies, high-density multiple-level-cell and 3D ash memory chips are emerging as ● Master Thesis Supervision Award
popular alternatives for embedded applications, but also introduce new challenges with respect from Taiwan Institute of Electri-
to reliability, performance, and endurance. To this end, we are pioneering the adoption of heal- cal and Electronic Engineering

leveling on real 3D ash to signi cantly enhance the lifetime of 3D ash; we have also proposed (TIEEE). (2013)

a software solution to reduce the write disturbance of real 3D ash memory. Concurrently, we are ● Two-year’s project grant from

the rst team to propose employing direct hardware information (instead of using the indirect National Science Council for ex-

index “erase count”) to conduct wear leveling; this proposed solution can signi cantly outper- cellent junior research investiga-
form any existing wear leveling strategies, with considerably less computing power and RAM tors. (2011)
space usage.
● Assistant Research Fellow,
We also investigate the possibility of adopting the emerging byte-addressable non-volatile Institute of Information Science,
memories, e.g., PCM, ReRAM, and STT RAM, in embedded systems. Due to their non-volatility and Academia Sinica (2011 - )
byte-addressability, these emerging non-volatile memories could serve as both working memory
and persistent store. Thus, we propose the concept of a “one-memory system”, which adopts non-
volatile memory as its main memory and storage at the same time. Such a system could mitigate
the performance gap between the main memory and storage in computing systems. However, existing operating systems consider storage as
block devices, and manage main memory and storage separately. In order to take advantage of the one-memory architecture, we are redesign-
ing the memory management and storage systems of existing operating systems. At the same time, we are investigating the possibility of de-
signing a new le system that can take advantage of the byte-addressability of these emerging non-volatile memories to optimize the storage’s

capacity utilization and minimize redundant storage accesses, to save energy and improve performance.
Publications

1. Po-Chun Huang, Yuan-Hao Chang, Kam-Yiu Lam, Jian-Tao Wang, 6. Yuan-Hao Chang, Po-Chun Huang, Pei-Han Hsu, Lue-Jane Lee, Tei-
and Chien-Chin Huang, “Garbage Collection for Multiversion Index Wei Kuo and David Hung-Chang Du, “Reliability Enhancement of

in Flash-based Embedded Databases,” accepted and to appear in ACM Flash-Memory Storage Systems: An Efficient Version-Based Design,”
Transactions on Design Automation of Electronic Systems. IEEE Transactions on Computers, vol. 62, no. 12, pp. 2503-2515,
Dec. 2013.
2. Jian-Tao Wang, Kam-Yiu Lam, Yuan-Hao Chang, Jen-Wei Hsieh,
and Po-Chun Huang, “Block-based Multi-version B+-Tree for Flash- 7. Che-Wei Tsao, Yuan-Hao Chang, and Ming-Chang Yang, “Perfor-
based Embedded Database Systems,” accepted and to appear in IEEE mance Enhancement of Garbage Collection for Flash Storage Devic-
Transactions on Computers. es: An Efficient Victim Block Selection Design,” ACM/IEEE Design

Automation Conference (DAC), Austin, Texas , USA, Jun. 2-6, 2013.
3. Yuan-Hung Kuan, Yuan-Hao Chang, Po-Chun Huang, and Kam-Yiu
(Top Conference)

Lam, “Space-Efficient Multiversion Index Scheme for PCM-based
Embedded Database Systems,” ACM/IEEE Design Automation Con- 8. Ming-Chang Yang, Yuan-Hao Chang, Che-Wei Tsao, and Po-Chun

ference (DAC), San Francisco, California, USA, Jun. 1-5, 2014. (Top Huang, “New ERA: New Efficient Reliability-Aware Wear Leveling
Conference) for Endurance Enhancement of Flash Storage Devices,” ACM/IEEE
Design Automation Conference (DAC), Austin, Texas , USA, Jun. 2-6,
4. Yu-Ming Chang, Yuan-Hao Chang, Jian-Jia Chen, Tei-Wei Kuo, 2013. (Top Conference)
Hsiang-Pang Li, and Hang-Ting Lue, “On Trading Wear-leveling with
Heal-leveling,” ACM/IEEE Design Automation Conference (DAC), 9. Jen-Wei Hsieh, Yuan-Hao Chang, and Yuan-Sheng Chu, “Implemen-
San Francisco, California, USA, Jun. 1-5, 2014. (Best Paper Nomina- tation Strategy for Downgraded Flash-Memory Storage Devices,”
tion (12/787) - Top Conference) ACM Transactions on Embedded Computing Systems, vol. 12, no. 1s,
pp. 60:1-60:29, Mar. 2013.
5. Yu-Ming Chang, Pi-Cheng Hsiu, Yuan-Hao Chang, and Che-Wei
Chang, “A Resource-Driven DVFS Scheme for Smart Handheld De- 10. Yuan-Hao Chang, Cheng-Kang Hsieh, Po-Chun Huang, and Pi-Cheng
vices,” ACM Transactions on Embedded Computing Systems, vol. 13, Hsiu, “A Caching-Oriented Management Design for the Performance
no. 3, pp. 53:1-53:22, Dec. 2013. Enhancement of Solid-State Drives,” ACM Transactions on Storage,
vol. 8, no. 1, pp. 3:1-3:21, Feb. 2012.

75