[GRASSLIST:3851] Re: s.surf.idw help

[Gordon Keith]

Sounds like you are running out of swap space.

I gave up on s.surf.idw on my data set. After I gave it about 3GB of 
swap space it managed to process 3% of the data over a weekend, so I 
killed it.

If you have any luck with settings that work in reasonable time, let me 
know.

To monitor your swap usage you can use utilities like top, xosview etc 
(they're the ones I use, but there are many others that will do the 
job).

If you are running out of swap space it is fairly easy to create a swap 
file and add it to your current swap area:

su
dd if=/dev/zero of=/var/swapfile bs=1024 count=2048000
mkswap /var/swapfile
swapon /var/swapfile

Will create a 2GB (approx) swapfile called /var/swapfile, format it as 
swapfile and add it to the swap space.

The file can reside anywhere on the local file system, so long as it it 
created using the preceding commands. On a faster disk is of course 
better for performance. Swapfiles bigger than 2GB only work on very 
recent kernels, so I'd recommend sticking with 2GB or less and use more 
than one if you want more than 2GB extra swap space. (I used 2x2GB 
swapfiles and a 1.5GB swap partition when I was playing with 
s.surf.idw).

If you no longer need the swap space but need the disk space you can 
free it with:

su
swapoff /var/swapfile
rm /var/swapfile

The swapoff command will only work when there are no pages currently in 
the swapfile.  See man pages for mkswap, swapon and swapoff for 
details.


Hope this helps
Gordon



On Sat, 8 Jun 2002 01:09, Kevin Slover wrote:
> I am attempting to use r.surf.idw to create a finer resolution data
> set for GLOBE data.  Currently, I have imported the data at .001 deg
> X .001 deg res, and am trying to get to .0005 X .0005 deg res...it
> starts fine,
>
> reading in the input raster, however, will not read the entire
> raster...
>
> When it is reading in the raster, is it storing it to memory before
> starting the interpolation??  The first time I tried it, the message
> simply said KILLED.  I tried a second time, reducing the area of
> interpolation, and it completely froze up my computer.  I am using
> pre4 ( I think), I downloaded from CVS 2 wks ago, on a RH7.2.  Any
> thoughts??  I think I might be trying to do too much...just my first
> guestimate...
>
> thanks...

-- 

Gordon Keith
Programmer/Data Analyst
Marine Acoustics
CSIRO Marine Research
http://www.marine.csiro.au

"Computers are useless. They can only give you answers." 
- Pablo Picasso, 1968