On partitioning vs. placement rent properties

Abstract

Rent's rule can be derived by direct partitioning of the circuit netlist, by indirect partitioning of the placed layout, or by averaging the number of terminals for various equally large regions of the placed circuit. It is shown that all three methods may produce different results. After investigation of the fundamental reasons for these differences, three distinct effects can be identified. The boundary and the embedding effect is present with all placement approaches, though the embedding effect may be (partly) nullified by the grid effect that may occur with some partitioning-based placement algorithms.