r.surf.contour runs for days

[Jochen Albrecht]

Dear Netters:
There was a similar question sometime last week, however, I never saw it answer
ed.
Last Wednesday, I started r.surf.contour on a small area (2 x 3 km) with 10m re
solution (background is a SPOT scene). After 48 hours the system tells me, that
it is 10% done, a 'ps' command gave me something like 2600 minutes CPU time,
that this process has used. Extrapolating this figure would give me 18 days! An
answer to the above mentioned question asked for the parameters, that were used
 But: r.surf.contour does *not* ask for any parameters (but filenames); as oppo
sed to r.surf.idw, which ran for a few minutes only but with dissatisfying resu
lts.
One hint could be the raster file used. I converted isolines with v.to.rast.
Whereas the lines in the vector file were coninous, the "lines" in the raster
file looked more like a dotted line. There were (although quite regularily)
holes => the height values were not exactly neighboring each other. How this
comes, I don't know. Again, the conversion routine doesn't ask for any paramete
rs, so there doesn't seem to be much of a chance to do anything wrong.
By the way, does anybody know, how these routines are supposed to work? I mean
the algorithm and/or assumptions (how many neighbors are taken into account, et
c.) used.
Thanks for listening/reading

          Jochen

P.S.: Perhaps I should mention that the machine running that long is a Sparc2.