How much parallelism can be teased out of the NetBSD build process?

["Erik E. Fair" <fair%netbsd.org@localhost>]

make(1) is a pretty good dataflow analysis tool, if it is given 
enough information.

If one were building a cluster to do NetBSD builds, how big can it 
get before you have idled processors from insufficient work? Or, put 
another way, how much parallelism can we tease out of the NetBSD and 
pkgsrc build systems?

        pondering out loud,

        Erik <fair%netbsd.org@localhost>