r.cost

[Jim Westervelt]

r.cost will run for a very long time.   Your large map has forced r.cost
to go into a memory swapping mode that utilizes very little CPU time and gobs
of disk R/W time.    I played with r.cost this last winter to find some
techniques for significant speedups.  Unfortunately I know of no stats for
running r.cost on maps as large as 4.8M pixles.  I will however be making
the latest version available on moon soon.