Hi PNR,Originally posted in cdnusers.org by EngHan
If you are not already doing the following, it can help:
setNanoRouteMode -drouteStartIteration 0
setNanoRouteMode -drouteEndIteration 1
setNanoRouteMode -drouteStartation 2
setNanoRouteMode -drouteEndIteration 19
setNanoRouteMode -drouteStartIteration 20
setNanoRouteMode -drouteEndIteration default
#set back to default, if not eco route (e.g. in Celtic flow) will not work!
setNanoRouteMode drouteStartIteration default
After saying this, I ready miss the little program that companion Silicon Ensemble. Siliocn Ensemble can write out a db every few minutes, and that little program can view these results (with congestion map). I find this very useful as the "area that cause the congestion" can be in a very different location as the final congestion map. For example, somewhere in the layout has congestion. During search-and-repair, the congestion can "drift/Expand". When the congestion drift toward some macros (esp at the corner), the congestion become worse, and that is what you get at the end of routing. Instead of resolving the congestion at the corner of the macro, it is more effective to solve it at the root cause; but this is possible if you can see the root cause in the first place. A pity that SOC does not provide users this useful methodology to resolve congestion.
However, note that we can throw out intermediate db during optDesign, so if final congestion map and global congestion map are matching, it is a way to detech root cause of congestino.