"Last year's clock contest led to intensive discussions with the ASIC and microprocessor design communities. ASIC clocking requires efficient tools which focus on clock power reduction, while robustness is the top concern of microprocessor designers," said Cliff Sze, the contest chair and research staff member at the IBM Austin Research Laboratory. "We redesigned the contest by making it closely align with real microprocessor needs."
Arizona State University contributed its Predictive Technology Model (PTM), which was used together with open-source Spice simulators to provide a common framework clock circuit simulations. A Monte Carlo methodology with 500 Spice simulations was performed.
"With the release of benchmarks from IBM and Intel, evaluation of exact clock latency using Spice simulations, and the realistic clock skew constraints, this contest has essentially captured real concerns of industrial clock synthesis problems," said Mustafa Ozdal, a researcher from Intel.
The primary objective of the contest was to create the most power-efficient design that met the timing constraints. Markov's winning team, including doctoral candidates Dongjin Lee and Myungchul Kim, created a design called Contango, which was four times more power-efficient than the design of the team that took second place.
"The top teams in the 2010 contest pursued very different strategies, including clock meshes and clock trees. So, the results will be interesting to industry experts who are thinking of possible power-performance trade-offs," Markov said. "For instance, our skews were often smaller than those by the second place team. However, their runtimes were in seconds, whereas ours were in hours."
Second place went to CNSrouter, created by a team from the lab of professor Evangeline Young at Chinese University of Hong Kong. CMSrouter was created by doctroal candidates Linfu Xiao, Zaichen Qian, Zigang Xiao and Yan Jiang. Third place went to NTUclock, created by doctoral candidates Xin-Wei Shih, Hsu-Chieh Lee, Kuan-Hsien Ho in the lab of professor Yao-Wen Chang from National Taiwan University.