[GRASSLIST:1703] Re: GRASS on clusters

[Markus Neteler]

On Wed, Apr 04, 2001 at 07:01:50PM -0700, Rich Shepard wrote:
> On Wed, 4 Apr 2001, Lars Bromley wrote:
> 
> > I'd like to reopen Dr. Rich Shepard's year old message (see below) to this
> > list, regarding using GRASS with a cluster.  I have a big project coming
> > up and am hoping to set up a cluster to help speed up the workload. Have
> > any of you experimented further with GRASS and clusters? Messages to the
> > listserv indicate that it is indeed possible, but I didn't see if anyone
> > had actually tried it. If anyone has, would they mind giving me a clue as
> > to how it might turn out? Does it speed things up, or is it more hassle
> > than its worth? I am using linux as my OS and will be using Beowulf as my
> > clustering software, and have six pentiums to start with.
> 
> Lars,
> 
>   Some day, I'd like to be able to afford the port. The parallelizing
> compiler is very expensive (at least on my budget), but it is do-able. Right
> now, I have higher priorities on my GRASS time, and I've not read anything
> from anyone else about putting together such a port.
> 
>   There would be a large time investment, too, to reorganize the code so it
> could be parallelized. Candidly, I've no clue what that would require.
> 
> Rich
> 

excuse me to indrude here... Just a hint:
GRASS 5 contains the "gmath" library which is a wrapper to LAPACK/BLAS.
LAPACK/BLAS itself is a sophisticated mathematical library which exists
in parallelized form (as far as I know). See:
http://www.netlib.org/lapack/

Like that cpu-intensive parts in GRASS code could be rewritten to utilize
the "gmath" lib (src/libes/gmath/).

Maybe that's a starting point?

Regards

 Markus Neteler

PS: Some "gmath" details can be found in the "GRASS 5 programmer's manual":
    http://www.geog.uni-hannover.de/grass/grassdevel.html#prog