[GRASSLIST:3216] Re: GRASS-Python, or, Alber'salgorithm?/r.proj with big files

[Len Coop]

Gordon,
Thank you, that did it! I only had 1GB swap, with 4BG more that you
showed me how to add, the process
is now taking ram (.5GB) plus 1.9GB swap (still creeping upwards at 20% reprojected at this point)
, and is chugging along nicely.
Luckily I have a RAID 5 SCSI array which is pretty fast.
Well done!
Len

Gordon Keith wrote:
> 
> On Tue, 26 Feb 2002 07:39, Len Coop wrote:
> > I forget the number of rows-cols that I was able to re-project when I
> > bumped my PIII 550 box
> > from 256 MB to 384 MB, but it was less than the 20000x24000 (90 MB)
> > file I would like to reproject at the moment.
> >
> > My new box (PIV 1.9 Ghz) has .5 GB Rambus memory,
> > which would be expensive to toss and replace with 1 GB, but I suspect
> > that would NOT be enough for these NLCD files. As it goes now, I
> > CRASH the box running r.proj, requiring a cold boot, which I have
> > never run into before with Linux (the process should die and not take
> > the whole operating system down with it). Here is the final thing I
> > see (this after downsizing output resolution) before the box freezes:
> 
> What size swap do you have?
> 
> I found that grass would crash my linux box when I ran out of swap
> space on my .5GB RAM machine (I have a 1.5GB swap partition) so I added
> two 2GB swapfiles and it hasn't been a problem since (yet). So far I
> haven't needed much more than 3GB swap.
> 
> su
> dd if=/dev/zero of=/var/swapfile bs=1024 count=2048000
> mkswap /var/swapfile
> swapon /var/swapfile
> 
> repeat for /var/swapfile2
> 
> You'll have to add the swapon command somewhere in the boot sequence if
> you want it add the swap files when you reboot - I haven't bothered as
> it's easy enough to add when needed and easy to trash the swapfiles
> when I have more need for disk space.
> 
> Of course swap is much slower than ram but these big jobs take long
> enough I prefer to do them overnight anyway.
> 
> --
> 
> 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

-- 
Leonard Coop
Research Associate
Entomology Dept & Integrated Plant Protection Center
2046 Cordley
Oregon State University
Corvallis OR 97331-2907
Phone 541-737-5523
Fax   541-737-3080
http://osu.orst.edu/dept/entomology/coopl