[GRASS-user] 64 bit or parallel processing

Glynn Clements glynn at gclements.plus.com
Wed Feb 28 21:27:10 EST 2007


Hamish wrote:

> Any thoughts on gains that could be made by MPI'ing the segmentation
> lib? Do do modules using that usually do so for memory needs not
> processing speed?

Modules which use the segment library normally do so because they
access the raster data in an order other than top-to-bottom.

If an algorithm reads the data in a linear fashion, there's no point
in using the segment library.

Ultimately, we need to look into replacing the core raster I/O code. 
However, this needs to be done incrementally; we can't afford to put
everything on hold while we re-write everything which uses
G_{get,put}_raster_row() etc (i.e. most of GRASS).

-- 
Glynn Clements <glynn at gclements.plus.com>




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