[GRASS-user] Re: [GRASS-windows] Virtual memory available to cygwin GRASS

[Glynn Clements]

Luigi Ponti wrote:

> > If the latter,
> > you don't see grass using much memory because it is fairly efficent
> > most of the time and doesn't need to- especially the core GIS and
> > raster parts of it. When you consider the amount of RAM+CPU power
> > typically available back when that code was written, it isn't
> > surprising that it was done in such a way.
> 
> Thanks Hamish, I see your point. What I don't quite understand is why 
> CPU usage always goes up to 100% when running GRASS commands, while 
> allocated memory is always about 25% -- flat, no peaks.

Any process will use 100% CPU unless either it can process the data
faster than the OS can provide it or it has to contend for the CPU
with other active processes.

The only time the CPU will be idle is if no process is ready to run,
i.e. if all processes are blocked waiting for input, whether user
input or data from a disk, network connection, external device, etc.

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