From: mstaben@comtch.spk.wa.us (Matthew Staben)
Newsgroups: comp.os.os2.misc,comp.sys.ibm.pc.hardware,comp.benchmarks
Subject: Re: Text scroll benchmark
Keywords: text scroll benchmark window
Date: 5 Sep 92 04:22:36 GMT
Organization: Waffle BBS at CompuTech Spokane, Washington

ochealth@unixg.ubc.ca (ochealth) writes:

> In article <14gnjd+.jps@netcom.com> jps@netcom.com (John Serafin) writes:
> >
> >I am proposing a text scrolling benchmark.   Although most computers can
> >scroll text much faster than it is possible to read, scrolling delay can
> >be quite objectionable during interactive modem sessions.   Scrolling text
> >in a window in a GUI environment can take up so much CPU time that full
> >modem throughput is not realized.   I have made some measurements and my
> >results are at the end of this article.   My motherboard is an ISA 486
> >from Intel with an Intel chipset.   For some reason, vector oriented
> >graphics run faster on Taiwanese motherboards with the same SVGA card.
> >Therefor other people with ProDesigner IIs may get better results.
> >
> >I would be particularly interested in seeing how various 8514, XGA, and TIGA
> What surprises me about OS/2 is how poorly screen writes are done.
> Perhaps it's the Trident driver that's poorly coded. I am running
> 1024x768 256 mode.
> 
> The Trident card is quite good hardware, and their driver support is good
> (just wish they'd HURRY UP with fixing these beta drivers!)
> Normal VGA mode is very quick when scrolling, but 1024x768 sucks.
> Everything else about 1024x768 is quick. I'm also using a 486 33MHz 12 meg
> machine, so that's not causing performance problems.
> 
> The reason scrolling is slow is that OS/2 seems to write one character at
> a time, or maybe a line at a time. This slows things to a crawl in 1024x768
> mode. *However* screen updates for a large area of text are quite fast.
> In a windowed TE/2 session, 2400 bps, the line by line scrolling sends
> Pulse up to 100% CPU. But if I click the mouse in the window for a few second
> the scrolling stops, and when I release the mouse, the whole window updates
> in a flash. Pulse shows much reduced CPU usage.
> 
> I notice that fat pig X Windows on a Sun 3/60 is much faster(screen) than my
> 486. X is in C, the 16 bit PM stuff is all assembler. What gives?
> Well if you watch an Xterm closely, it updates a terminal window in
> a kind of "burst mode", kind of "lazy writes" for the screen.
> (BTW, the 3/60s have unaccelerated framebuffers)
> 
> I'll wait for IBM to tweak the video some more, before I think of
> a grahics accelerator.
> 
> 
> 
> >jps@netcom.com   |  Operating an automobile is more like riding than driving
> 
> 
> -- 
> _____________________________________________________________________________
> jpm: ochealth@unixg.ubc.ca         
>                             Happily using OS/2 2.0 because MS Windows isNT __
>                                                       Insert VapourFeature ^^

 
I use a Tseng4000 chipset (it required the VSVGA/VGA fix) and am using 
the 1024x768x256 interlaced mode and my text windows are quite fast.  In 
fact, I find excellent performance in a 50 line vga text-emulated box.  
Sure, it goes slower than the character generator does, but not much.  
 
Let's put it this way.. I sometimes can't hit ^s fast enough during a 
directory - thus having to do it allllllll over again!
 

mstaben@comtch.spk.wa.us
 
- A warning to anyone, still in command...