On Jun 7, 2005, at 10:40 AM, przybyls@engr.arizona.edu wrote:

> I'd like to add something else to this also. Most probably already  
> knew
> this, but I'm just putting it into perspective. Mac OS X = Darwin +  
> Aqua.
> Darwin has already been strongly supported on x86 platform with very
> little security issues. Many use Darwin x86 as their server  
> platform also.
> I believe this switch to Intel is rather triggered by the support  
> of x86
> systems by Darwin. For awhile now x86 has only been supported as a
> reference implementation. I think that it has come along so well that
> Apple is now in the position where their x86 support of Darwin is  
> as good
> as the PPC support.

This is so far from true that I barely know where to begin. Darwin/ 
x86 has very limited support and runs on a small handful of x86  
motherboards. It is also quite finicky about the ATA controller, CD- 
ROM, NIC and GPU. I don't think the x86 version will boot on a  
motherboard made after 2002, and its support for motherboards before  
that time is spotty.

I don't know anyone running darwin/x86 in any serious way. There are  
a few folks on the OpenDarwin list who do use it as their daily box,  
but they are extremely aware of its limitations.

Apple truly did keep this as a reference implementation for making  
sure their code was endian "clean." They didn't spend any time at all  
making sure it ran on every motherboard out there. Their plan is to  
only support their own motherboard. The only way to get it on other  
boxes is for some enterprising coders to learn IOKit and write the  
drivers. I'm sure there are some talented folks on this list who are  
capable. :-)

> Anyway, I believe the biggest hurdle would be porting Aqua to x86. A
> proof-of-concept must have been completed before the proposal, so I  
> also
> believe that they'll have it in release-candidate state very  
> easily. OS
> users will probably not see any difference between the OS X they knew
> before and whatever is released on x86.

In the keynote speech, Steve Jobs admitted that there was a  
corresponding x86 release for every single PPC release all the way  
back to 10.0. Therefore, there is no hurdle to porting Aqua and the  
other GUI elements. The job is already done.

>
> I am not happy about the move from PPC to x86 either. I believed  
> PPC RISC
> was a remarkable balance of performance and stability. I was  
> especially
> excited at the possibility that Apple might use the new Cell PPC.  
> Instead,
> they are going to Intel and who knows if they'll ever see the dual- 
> core
> Intel.

Apparently the roadmap that Apple saw wasn't very good. I'm certain  
this has everything to do with IBM's reluctance to build any low- 
power versions of PPC that were suitable for a laptop or notebook  
style device.

This isn't Apple's fault any more than it was their fault that  
Motorola couldn't keep up.

cr