Modeling and minimization of routing congestion

Maogang Wang, Majid Sarrafzadeh
2000 Proceedings of the 2000 conference on Asia South Pacific design automation - ASP-DAC '00  
Abstract| Typical placement objectives involve reducing net-cut cost or minimizing wirelength. Congestion minimization is least understood, however, it models routability most accurately. In this paper, we study the congestion minimization problem during placement. First we pointed out that the bounding box router used in 12 is not an accurate measurement of the congestion in the placement. We use a realistic global router to evaluate congestion in the placement stage. This ensures that the nal
more » ... placement is truely congestion minimized. We also proposed two new post processing algorithms, the ow-based cell-centric algorithm and the net-centric algorithm. While the ow-based cell-centric algorithm can move multiple cells at the same time to minimize the congestion, it su ers large consumption of memory. Experimental results show that the net-centric algorithm can e ectively identify the congested spots in the placement and reduce the congestion. It can produce on an average 7:7 less congestion than the method proposed in 12 . Finally, we use a nal global router to verify that the placement obtained from our algorithm has 39 less congestion than a wirelength-optimized placement obtained by TimberWolf commercial version 1.3.1.
doi:10.1145/368434.368601 dblp:conf/aspdac/WangS00 fatcat:vz7nt5vewrhozj4plswlk5l6py