Re: How viable is Cocoa development?

FROM : Rainer Brockerhoff
DATE : Sat Jan 26 17:37:50 2002

At 16:44 +0100 26/01/2002, Ondra Cada wrote:
> >>>>>> Rainer Brockerhoff (RB) wrote at Sat, 26 Jan 2002 12:32:40 -0200:
>RB> However, one could also argue that this would have made Carbonized apps
>RB> even slower than they are now, with all that dynamic-dispatching stuff
>RB> going on underneath, and no way to get around it
>
>Since I have first-hand experience with "all that dynamic-dispatching stuff"
>on MC68040/25/32MB and even i486/66/20MB, I can be pretty positive it is
>*NOT* the cause of the slowness of something on a G4/733/0.5GB RAM machine...

Agreed that dynamic dispatching can work quite well even on slow CPUs if not overdone. I've done a medical monitor which did dynamic dispatching on a 4Mhz Z80 (assembly language, however), just to top your experience :-)


>I do agree that OS X _is_ slow, even on those supercomputers. "All that
>dynamic-dispatching stuff" can't be blamed though, the problem is elsewhere.
>I have some suspicions, but since they are not proven, I won't go into
>details... well, one thing's proven: check archives for the thread "Ways
>Apple COULD optimize -setNeedsDisplay"!

Well, I too have heard that text drawing is slow. However, the more Cocoa APIs I use in my application to get file data and such, the slower it gets, in the sense that it takes much longer _before_ displaying something than if I collect the information with Carbon or BSD calls.

My suspicion is that NSFileManager and NSWorkspace do lots of wasteful stuff like creating temporary arrays, strings, arrays of strings, dictionaries and so forth inside loops... that's why I try not to use them if I need speed.



--
Rainer Brockerhoff  <<email_removed>>
Belo Horizonte, Brazil
"I love deadlines. I love the whooshing noise they make as they go by" (Douglas Adams)
http://www.brockerhoff.net/ (updated Jan. 2002)