Overhead for independent net approach for Global Routing

Global Routing is one of the major Electronic Design Automation steps and it is classified as an NP-hard problem. We verified that 61% of the nets in ISPD 2008´s benchmarks are shorter than 128 length units. We propose a method to cluster these nets using an independent net approach to perform global routing in massively parallel systems. We demonstrate that separating nets in clusters according to its length and processing it in parallel can reduce by 67 the processing time for collision detection, if compared with a sequential non-clustered analysis.