• Youhui ZHANG

• Professor

• Department of Computer Science and Technology

• Joined Department: 2002

• Email:zyh02@tsinghua.edu.cn

• URL:https://craft.cs.tsinghua.edu.cn/

• Phone:010-62785592

• Fax:010-62771138

Education background

Bachelor of Computer Science & Technology, Tsinghua University, Beijing, China, 1998;

Ph.D. in Computer Architecture, Tsinghua University, Beijing, China, 2002.

Social service

Deputy Director of Institute of High Performance Computing Technology, Tsinghua University.

Areas of Research Interests/ Research Projects

Research Areas

Micro-architecture, Cluster computing, and User-level Virtualization technologies

Courses

Storage Technology Foundations (Undergraduate);

Assembly Language Programming (Undergraduate);

Computer Organization and Architecture (Undergraduate).

Teaching Profile

At present I am teaching three courses per year, which is open to all undergraduates in the Institute of Information Science. All courses belong to the field of computer architecture and my teaching philosophy is to help students develop a conceptual framework of the computer architecture and the underlying programming language. As far as possible I also guide students to find and grasp the rules and necessities behind the technology advances.

Currently, the course ‘Assembly Language Programming’ has been entitled to National Excellent Resources Sharing Course by Chinese MOE. And the course ‘Computer Organization and Architecture’ has been supported by the MOE-Intel Excellent Course Plan.

Research Projects

The National High-Tech R&D Program of China (The 863 Program): Development of Test and Evaluation System of Cloud Computing (2013-2015);

The MOE-Intel IT Program: Research on the Transparent SaaS usage model of Existing Teaching Software (2011-2013);

The National High-Tech R&D Program of China (The 863 Program): Overall Technologies of High-end Fault-tolerance Computers (2008-2011);

The National Natural Science Foundation of China： Architecture Research of Storage Chip-Multiprocessors with Object-data Support and Dynamic Function-extension (2008-2010);

The National Basic Research Program of China (The 973 Program)：Research on the Virtualization of Resources from Multi-computers (2007-2011);

The National High-Tech R&D Program of China (The 863 Program): Research on the Portable and Personalized Software based on Virtualization and Network Services (2006-2008);

The National High-Tech R&D Program of China (The 863 Program): Middleware of High-performance Clusters (2002-2004);

The National High-Tech R&D Program of China (The 863 Program): Development of a 32-bit High-performance Embedded Processor (2002-2004).

Research Status

1) My group has carried out the research on the design of application-oriented customized processor, which is believed as one promising method to solve the development bottlenecks of computer architecture, including the power wall and the lower energy-efficiency. We present a systematic approach to enhance a preliminary customizable processor-core with some common architecture features (not totally application-specific) to adapt to some high-performance computations, and the programming flexibility can be still kept. Moreover, the corresponding simulation tools have been developed.

Now we selected the kernel computation of the ‘Global Climate Change’ numerical simulation as the representative goal and have implemented the FPGA prototype of the customized core. A preliminary comparison with an X86 server core (with the same CMOS technology) also shows that the design can achieve an order of magnitude higher performance per watt; its application performance is about 54% of that of X86 while the chip area is only 1/70. In addition, with the cooperation of NAIST, a functional unit (FU) array based architecture for the weather forecasting application (GRAPES) has been prototyped. It can achieve a per-core average IPC of 12.3 within a 20-stage FU array processor, which has a 5.8x power-efficiency boost than the many-core processor (MCP) of a same process technology.

One of the simulation tools we have implemented, the HW(FPGA) /SW hybrid Network-on-chip simulator has been used for the design verification of inter-connection structure of the high-end fault-tolerant computer, which is supported by one of the key 863 Program projects in the 11th Chinese Five-Year Plan.

2) My group also carries out the research on application-level virtualization. Now we have developed a prototype that any user can access his/her personalized Windows software on any compatible networked PC without installation, which employs the portable device and/or network storage as the storage location and is totally transparent to the existing software. It has been applied to the instant software deployment in Corona, a cloud computing system for research at Tsinghua. Moreover, it enables to store the software on the cloud and run it on the local computer, which can convert the existing software into network services transparently.

Honors And Awards

State Council, The People's Republic of China: High Performance Cluster Computers and Massive Storage Systems, National Award for Science and Technology Progress, 2nd Class (2007);

Ministry of Education, The People's Republic of China: Performance Analysis of High Performance Computers, Award for Science and Technology Progress, 1st Class (2009).

Chinese Institute of Electronics, Award for Science and Technology: Performance Analysis of High Performance Computers, Award for Science and Technology Progress, 1st Class (2009).

Academic Achievement

[1] Youhui Zhang, Gelin Su, Weimin Zheng. Converting Legacy Desktop Applications into On-Demand Personalized Software, IEEE Transactions on Services Computing, Vol.3, No.4, 2010. 306-321.

[2] Youhui Zhang, Xiaoling Wang, and Liang Hong, Portable Desktop Applications Based on P2P Transportation and Virtualization. Proceedings of the 22nd Large Installation System Administration Conference (LISA '08), San Diego, CA, 2008, pp. 133–144.

[3] Youhui Zhang, Yanhua Li, Weimin Zheng. Automatic Software Deployment Using User-level Virtualization for Cloud-Computing. Future Generation Computer Systems（FGCS）,Vol.29 N0.1. Jan 2013. 323-329

[4] Zhang YouHui, Qian ZiQiang, Zheng WeiMin. Employing intelligence in object-based storage devices to provide attribute-based file access. SCIENCE CHINA-INFORMATION SCIENCES. Vol.56, No.3. Mar 2013. 1-10.

[5] Youhui Zhang, Gelin Su&, Weimin Zheng. A User-space File System for On-demand Legacy Desktop Software, SCIENCE CHINA-INFORMATION SCIENCES, Vol.54，No.6，2011. 1142-1150.

[6] Liu Li, Zhang YouHui, Liu Li, Yang Guangwen, and Zheng WeiMin. Efficient Monte Carlo-based Options Pricing on Graphics Processors and Its Optimizations. SCIENCE CHINA Information Sciences, Vol.53, No.9, 2010. 1703-1712.

[7] Youhui Zhang, Peng Qu, Yanhua Li, Hongwei Wang, Weimin Zheng. Cache Optimizations of Distributed Storage for Software Streaming Services. ICA3PP 2013: 458-467

[8] Youhui Zhang, Yu Gu, Hongyi Wang, and Dongsheng Wang. Virtual-Machine-based Intrusion Detection on File-aware Block Level Storage. Proc.18th International Symposium on Computer Architecture and High Performance Computing (SBAC-PAD'06), Ouro Preto, Brazil, pp. 185-192.

[9] Youhui Zhang, Dongsheng Wang. Research on object-storage-based intrusion detection. Proceedings of the 12th International Conference on Parallel and Distributed Systems (ICPADS'06). 2006.

[10] Fan Jie&, Jiang Song, Shu Jiwu, Zhang Youhui, Zhen Weimin. Aegis: Partitioning Data Block for Efficient Recovery of Stuck-at-Faults in Phase Change Memory. Proceedings of the 46th Annual IEEE/ACM International Symposium on Microarchitecture (Micro 2013). 2013.