Date:	Thu, 12 Dec 1996 16:46:31 +0200 (EET)
From:	Indrek Mandre <indrek AT warp DOT edu DOT ee>
To:	jd marrow <pachydrm AT ix DOT netcom DOT com>
cc:	djgpp AT delorie DOT com
Subject:	Re: performace questions
In-Reply-To:	<01bbe739$d1ef65a0$78335dcf@monkey>
Message-ID:	<Pine.LNX.3.91.961212163501.424A-100000@warp.edu.ee>
MIME-Version:	1.0

On 11 Dec 1996, jd marrow wrote:

> 
> greetings...
> 
> i've recently begun using djgpp for a variety of things, from personal
> projects to prototypes of 'things' that will eventually be moved to other
> [less savory :)] platforms...
> 
> i've run into a 'problem', however, regarding irratic performance (even
> within the same run) under win95 in a dos box and "win95-dos" (i'm using
> allegro for grfx):
> 
> = a 3d program, for eg, will run sometimes at 32 frames-per-sec, and then
> at other times at 20 frames-per-sec, although it's doing exactly the same
> thing...
> 
> = a program that manipulates bitmaps will also operate at different
> rates...
> 
> why might this be? what exactly is LOCK_VARIABLE supposed to do? how can i
> avoid this sort of problem?
> 
> i /suspect/ that the problem might be related to [virtual?] memory
> management -- although my laptop has 24M and my desktop 48M -- and wonder,
> if this is the case, how i work around the problem...
> 
> thanx VERY much in advance...
> 

I have the same problems - I made a graphics program and it slows down
sometimes - that makes it to jump. At my case it was most awful when
I moved mouse - even in pure DOS, under 95 it was terrible. I
didn't find any good way. I'm sure your program waits for v. retrace.
The programs speed depends a lot on that. It helps when you put
in cycle usleep (10000), and try to manipulate with it and
vetical retrace waiting. It helped for me a little. True it took
my program from 35 fps to 30 but it became smoother.

Indrek Mandre
indrek AT warp DOT edu DOT ee
http://www.ttg.edu.ee/~indrek

PS: My program (640x480x256) is under DOS 35 and under Linux 25-30 fps :)

- Raw text -