[Ham-Mac] LoTW and Mac OS X 10.6 Snow Leopard

[Jack Brindle]

Interestingly, maybe not. It seems the wider math for pointers (64  
bits vs 32 bits) tends to wipe out any speed advantage. Plus the  
kernel doesn't actually need to manage more than 4GB of memory. When  
you add to that the memory data paths may be 32 bits, which requires  
two fetches for 64 bit pointers, we can see the potential for slow- 
downs. It seems the extra registers in the CPU you get when the 64-bit  
flag is enabled may not counteract the rest of the system design. I  
bet down the road when we have 64 or 128 bit cpus and memory data  
paths things will scream.

The Apple developer information for 32 vs 64 bits is rather  
interesting. 64 bits for apps that need it and large memory systems is  
worth while. For smaller systems it may not be. That's why they  
enabled it on big servers but not on consumer systems.

On Sep 1, 2009, at 11:35 PM, David Ferrington, M0XDF wrote:

> Because in theory, it will be much faster.
> 73 de M0XDF
> -- 
> In theory, there is no difference between theory and practice,
> but in practice there is.
>
>
> On 2 Sep 2009, at 05:20, Jack Brindle wrote:
>
>> Why would you go to the 64 bit kernel?
>
>
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