Whaaaat?? 64-bit Kernel and Extensions: No

Mark,

Nice post ... this is interesting because Windows environments often ask the same things. Most of which have to do with the hardware, not the O/S itself.

The terms 32-bit and 64-bit refer to the way a computer's processor handles information. In most all cases, the 64-bit version of and O/S will handle data faster, due to the the way it's processed in the hardware.

64-bit is also a term given to a generation of computers in which 64-bit processors were the norm.
(This is why you have had 64 bit processors without actually using 64bit data from the prior o/s..)

64-bit CPUs have existed in supercomputers since the 1960s and in RISC-based workstations and servers since the early 1990s. So in other words, (IBM, Sun, Cray, SGI..etc..)

In 2003 they were introduced to the (previously 32-bit) mainstream personal computer arena, in the form of the x86-64 and 64-bit PowerPC processor architectures.

Without further qualification, a 64-bit computer architecture generally has integer and addressing registers that are 64 bits wide, allowing direct support for 64-bit data types and addresses.

However, a CPU might have external data buses or address buses with different sizes than the registers, even larger (the 32-bit Pentium had a 64-bit data bus, for instance). The term may also refer to the size of low-level data types, such as 64-bit floating-point numbers.

I believe this explains answers to your questions. Let us know if you have more around this. :P

For reference --- http://en.wikipedia.org/wiki/64-bit

No --- it was your o/s at the time ..

There are Intel Xeon Macs that certainly contain 64 bit cores -- but the O/S was the limitation due to the lack of 64 bit support.
(64 bit support has only become ever more apparent in the last 3-5 years ...)

in May of 2004 SGI Realeased a 64 bit Hardware/Software configuration called the Altix 3000.... That was still fairly new in the realm of 64 bit architecture, but it used Intel Itanium (even before the ones in your Mac...) processors .... and the Linux Operating system was managing all the 64 bit hardware stuff ...




It's completely possible to have 64 bit hardware inside and never use it, because the o/s won't do it. (cant use features, take advantage of special things etc...)

It's completely possible to have a 32 bit hardware inside and never use 64 bit from the O/S because your hardware cannot support it...


In the case of Quad Core Intel Xeons... yes .. they have been installed in Mac's for a while now, but until the new o/s came out, very little of the 64 bit technology/functionality could be taken advantage of.

The even newer Mac's with Nahelem processors, are even better!

[Mark Palmos] "BUT I had though TIGER was 64 bit,"

I dont believe !0.4 was 64 bit. 10.5 was part 64 bit but many core components like quicktime were still 32 bit. 10.6 is fully 64 bit.

[Mark Palmos] "and that the MacPro I bought two years ago was 64 bit"

Capable of 64 bit yes.

[Mark Palmos] "Im sure there are many others of you who are shocked by that, especially since tests show the 64 bit to be a more than 25% speed improvement for rendering. "

you FAIL to understand that the video editing software must ALSO be 64 bit. Even the new FCS3 is NOT 64 bit.

[Mark Palmos] "Anyone care to offer a layperson's explanation of why my system is forced to 32 bits when OSX is supposedly 64"

Because MOST software out there is NOT 64bit so for compatibility reasons it does not.




There are no "technical solutions" to your "artistic problems".
Don't let technology get in the way of your creativity!

In this web page you can find simple explanations about 32-64 bits (Kernel and Applications) in OSX snow leopard:

http://www.Ahatfullofsky.Comuv.com / english / programs / sms / sms.html


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Why would Apple Do That?

The problem is compatibility with third-party Drivers. Some programs are so deeply intertwined with the OS that they reach deeply into its bowels and modify its core, The Kernel - these Drivers are called Kernel extensions (or kext).

Rule

32-bit processor can only run 32-bit stuff.
64-bit processor can run 32-bit and 64-bit stuff.
(stuff can be system, Kernel, Applications, Drivers, Etc)

I know you need a 64-bit processor to run 64-bit anything

On a 64-bit processor:
32-bit Kernel can run both 32 and 64 bit Applications.
64-bit Kernel can run both 32 and 64 bit Applications.

32-bit Kernel can only load 32-bit kexts (Kernel extensions).
64-bit Kernel can only load 64-bit kexts (Kernel extensions).

If a program uses 32-bit Kernel extension (like the PC emulator vmware fusion) then that extension will not run in a 64-bit Kernel. So until they update their kext the program will not run if you start the Kernel as 64-bit. However the program will run late if the Kernel stays 32-bit, Even if the application itself is 64-bit)

The ability to start up with a 64-bit Kernel (by booting while holding 6 and 4) is meant for developer so they can start developing 64-bit Kernel extensions. The average user never really 'needs' to be in 64-bit Kernel - in fact, You would not want to have a problem with your 32-bit Kernel extension, Would you?