As CMOS transistors continue their scaling downward, multiprocessor-system-onchips (MPSoCs) will likely be used in many applications, as they often permit higher performance and better power efficiency than uniprocessor architectures. However, MPSoCs can have high power density and temperature, which degrade reliability and increase packaging and cooling cost. Techniques such as processor throttling are being considered to prevent the chip from reaching an unsafe temperature at runtime. However, runtime throttling can have undesirable performance consequences. The problem is particularly acute for real-time applications, which demand predictable timing behavior.
This talk discusses two solutions for the problem of assignment and scheduling of real-time tasks being executed on a MPSoC in order to minimize the chip's peak temperature. The first solution is an exact solution based on a mixed-integer linear programming (MILP) formulation. The formulation considers both spatial and temporal variations in power density, and relies on a phased steady state thermal analysis technique that is directly integrated within the MILP formulation. The second solution, targeting at larger problem instances, is a heuristic in which the actual method of computing the temperature profile can be adjusted for different physical parameters. Experimental results show that the solutions outperform existing approaches.
Sharon Hu received B.S. degree from Tianjin University, China, M.S. degree from Polytechnic University of New York, and Ph.D. degree from Purdue University. She worked for General Motors Research Labs for 4 years before starting her academic career. She has published over 120 papers and obtained a number research grants from both the U.S. government agencies and private industry. She received the CAREER award from NSF in 1997. A paper co-authored by her received the Best Paper Award from the Design Automation Conference in 2001. Another of her paper was selected as one of the Most Influential Papers of 10 Years of the DATE conference (between 1998-2007). She has served as an Associated Editor for IEEE Transactions on VLSI Systems and ACM Transactions on Design Automation of Electronic Systems. She was the Technical Program Co-Chair of the International Symposium on Hardware/Software Codesign and the General Co-Chair of the same conference in 2002. She has also been invited to serve on the program committees of many conferences such as DAC, ICCAD, DATE, and ICCD.