[GRASS5] [bug #3087] (grass) high cpu usage

[Glynn Clements]

Maciek Sieczka wrote:

> >> this bug's URL: http://intevation.de/rt/webrt?serial_num=3087
> >
> >> Subject: high cpu usage
> >
> >> GRASS Version: 6.0.0
> >>
> >> some commands, like d.zoom, d.what.rast or d.what.vect using about 50%
> >> or more of cpu resources. there is no problem with this in grass54. my
> >> cpu is pentium 4 2.8ghz.
> 
> > This is a known problem with all programs which use the mouse.
> 
> But a very serious one and requiring a fix if possible.
> 
> I'm not the one who reported on this (that was another Maciek :) ) so I
> might not remember details, but as far as I know them guys use this machine
> (P4 2.8 GHz, 4GB RAM) as a server for 12 Linux stations during GIS/Grass
> classes and courses at the Wroclaw University. And when few users use any
> d.* simultanously command on Grass6 it causes a complete deadlock of the
> server and the only solution is to reset it. Which makes students, Grass
> newbies in most, doubt in Grass quality.

Yeah, various people have complained about this, but it has been
neither fixed nor reverted.

AFAIK, it's only required for the newer v.digit and d.what.vect, due
to the "form" library. The problem with the original implementation
was that the program would block while waiting for a mouse press.

A better solution would have been to leave the original (working)
mouse handling untouched and to have implemented the "enhanced"
version as separate operations. That way, only the programs which
actually need the new version would cause problems.

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