MacBookPro3,1 + Snow Leopard = 32 bits.

I thought I had edited that. I meant there is a difference between running some 32-bit apps in a 64-bit environment and running everything in a 32-bit environment.

Message was edited by: Tekneek

Tekneek wrote:
In my experience, there is a difference between running 32-bit apps in a 64-bit OS and running 64-bit apps in a 32-bit OS.

You cannot run 64-bit apps on a 32-bit operating system.

Where some of the unneeded confusion is coming from is a lot of people are thinking of the Windows world where you need the x64 Edition of the operating system to take advantage of the additional power of x64 CPUs. It's not the kernel in Windows x64 that's the big difference maker, it's the 64-bit versions of the libraries and the application frameworks that make most of the real magic happen.

In the OS X world this isn't the case, all the 32-bit and 64-bit goodness is wrapped up in one package and your applications get to take advantage of the benefits of x64 in the applications while still using the much more compatible 32-bit kernel.

Microsoft could have implemented a similar universal binary system and ended the separate editions but has chosen not to. This made business sense for them. Windows XP x64 was an afterthought that came years after Windows XP launched and was actually Windows Server 2003 in a Windows XP colored coating of paint. Vista suffered major development issues without considering the major undertaking of developing a UB system. Windows 7 needed to be out fast to recover from the Vista fiasco so it definitely wasn't the time. By the time Windows 8 rolls around there should be little reason to hold on to x86 and x64 should likely be the only edition.

For Apple, having already tackled the universal binary to manage transition from PPC to x86, had any easy path when addressing the x64 aspect of Snow Leopard and doesn't need to worry about 32-bit vs 64-bit editions.

A lot of people run x64 editions of Windows not because they need to, but "because they can". Microsoft and OEMs pays the price (particularly with Vista) because relative to the installed base they receive far more support calls on x64 than x86 editions. A large percentage of these issues are related to lack of x64 drivers for the x64 kernel, particularly for already existing hardware. Generally speaking manufacturers are unwilling to spend extra money to create new x64 drivers for products they had already been paid for. There's no financial incentive. Even today there is still a percentage amount of hardware, particularly on the "budget" end that doesn't have release quality drivers for x64 (or even none at all).

Apple has avoided this issue by delivering Snow Leopard with the 32-bit kernel enabled by default. Should you have a choice to boot the 64-bit kernel if you want to? In some hardware configurations you do, in other cases you don't.

The real key is that this was not a mystery. It was quite well publicized that the 32-bit kernel was the default shipping kernel prior to any of us purchasing Snow Leopard and it was also quite well discussed on which hardware configurations that x64 kernel use was an option and which ones it wasn't.

As stated previously, I thought I had edited that.

The problem for me is this : I have 64-bit capable hardware, and I would love to boot into it. Even if it didn't work well, had lots of problems, and I had to revert back. At least I can make that choice. Deciding for me is not the solution I would prefer, but unfortunately it is the path that Apple often chooses. I accept that, but it doesn't mean I have to agree that it is the preferred solution.

Message was edited by: Tekneek

mmh.. i am still convinced that nobody using a mac averagely will actually need the 64bit kernel and extensions... i still think SL is so far the fastest system (32bit kernel or not) i've ever seen...
maybe some things don't work out as nicely as they should (but we're on x.6.1 so... you know)
Logic crashed the other day after doing the update to 10.6.1 found out it was a permission problem after the install.. doesn't really bother me too much..

i saw benchmark tests between the 32 and 64 bit kernel and extensions.. there is like a 25% difference on application startups..i still think benchmark tests don't mean anything coz it very much depends on how your system is setup and what apps you are using...

i am running 64bit apps in SL and now also JAVA seems updated (relaxes me a lot =) and my guess is that after some updates we all will be able to press 6 and 4 keys to boot into 64 bit kernel... this system is though even without the kernel still a 64bit system.. .. otherwise there would be no 64bit app running...

*isn't it snappy enough? really?* ok i have to admit i searched for this issue on the macbook pro 3.1 just to find out how it would be running the 64bit kernel... there are some hacks that wouldn't work on this book... but others that may do... maybe you wanna google for netkas.org and boot64.efi and find something interesting and with a little workaround you maybe get it done (you'll probably need a hex-editor though) there are some ppl claiming to have had success on the macbookpro 3.1 running the 64bit kernel and extensions =) hurray..

What I mean is that I want to be able to CHOSE if I want to boot in 32bit or 64bit.
I don't want Apple decides this for me.
So.. I'm not asking to have the default boot to 64bit, but to be able to press 6+4 and boot!

Linux is 64bit, like windows. Except for some proprietary plugin, in gentoo you compile everything, so you can have a true 64bit.
Windows NEED to be 64bit, while OS X not. Because windows use 32bit of address to address everything. So in modern pc Vista 32 can only address about 3GB of RAM and they are not enough.

Maybe I can't write what I'm thinking (english is not my language..), but what I want is to have more freedom...

Tekneek wrote:
At least I can make that choice. Deciding for me is not the solution I would prefer, but unfortunately it is the path that Apple often chooses.

Please keep in mind that Apple nowhere suggests that it supports anything except specific Macs running Snow Leopard Server for the 64 bit startup mode. Some folks have discovered that they can use the same technique to start up some -- but not all -- Mac models this way. In this respect, it is like any other unsupported feature -- basically, you are on your own in figuring out how to do it or even if can be done, short of writing your own version of the OS.

BTW, there is more to it, at least from Apple's standpoint, than just if the CPU is 64 bit capable. For instance, take a hypothetical case in which Apple determines that other systems in some Mac model won't work well with a 64 bit startup. It could be anything from memory bus timing to heat dissipation (remember, this is controlled by the SMC). Let's also say that Apple determines these limitations could result in data loss or even shorten the service life of the Mac. Apple would be foolish to let users make the choice for this model & users would justifiably scream bloody murder if it did.

Simply put, don't confuse the specs of a part with the specs of a system.

{quote:title=R C-R wrote:}{quote
BTW, there is more to it, at least from Apple's standpoint, than just if the CPU is 64 bit capable. For instance, take a hypothetical case in which Apple determines that other systems in some Mac model won't work well with a 64 bit startup. It could be anything from memory bus timing to heat dissipation (remember, this is controlled by the SMC). Let's also say that Apple determines these limitations could result in data loss or even shorten the service life of the Mac. Apple would be foolish to let users make the choice for this model & users would justifiably scream bloody murder if it did.

I welcome this explanation from Apple, rather than baseless speculation. A valid technical explanation would certainly help.

It is speculation, but it is not not baseless. I haven't designed computers but I have designed & built much less complex analog systems. Part specs vs. system specs are a major consideration for any system designer & why prototyping & extensive testing are a necessity for a reliable design.

As for an explanation from Apple, since when does it or any other maker of similar equipment need to explain why something unsupported isn't supported? Do you understand what unsupported means?

Yes. We can agree to disagree then.

Gamesta wrote:
I too have a MBP3,1 which has the 64bit EFI.

I understand the need to sunset some systems but this one is not even 2 years old. I definitely would NOT have purchased the upgrade if I know my 18month old system was obsolete in Apples eyes.

Ima try to get a refund.

What exactly makes you think that your machine is "obsolete"? The fact that it uses 32bit kernel by default? What do you think you are missing out on?

In order to use 64bit kernel, you would have to have 64bit kernel-extensions and drivers. Apple obviously feels that consumer-machine are not ready for 64bits in those areas, so they use 32bit kernel by default. Apps are still 64bits, however.

I bought my Mac in 2007. Apple has since moved on in technology and design, yet I do not feel for one seconds that my computer is "obsolete" it handles the tasks I use it for just as well, if not better, than it did on the day I bought it.

In short: your machine is NOT "obsolete".

Why do you say there is no advantage to running a 64-bit kernel? Do you have any performance numbers to back this up?

There appear to be some significant performance advantages, as measured here:

http://macperformanceguide.com/SnowLeopard-Performance.html#NikonCaptureNX2

Gains of 30% over the 32-bit kernel were found in these tests. And that's a huge difference.

Krakatos wrote:

Gains of 30% over the 32-bit kernel were found in these tests. And that's a huge difference.

30% where? Most performance-benefits were apparent when compared to 32bit Leopard. When compared to 32bit Snow Leopard, the differences weren't that big (5% seems to be pretty typical figure).

And are those performance-benefits worth it, if it brings with it compatibility-issues? And I still don't understand why machine that runs 32bit kernel is "obsolete"....

Krakatos wrote:
Gains of 30% over the 32-bit kernel were found in these tests. And that's a huge difference.

Look again. The big differences were between Leopard & Snow Leopard, with 64-bit vs. 32-bit SL differences substantially smaller.

Also note that these tests were done on a Mac Pro with a quad-core "Nehalem" CPU, 12 GB of memory, & a 4 drive RAID. Don't expect much similarity between tests run on that very high performance setup & anything you would see with an iMac or especially a MacBook (Pro or otherwise), even ones with the fastest available Core 2 Duo CPU's & maxed out memory.

Even though all these Macs use 64 bit Intel CPU's, the Core 2 Duo & Nehalem architectures have substantial differences, among them being the latter's "Turbo Boost" technology (which can dynamically boost the clock rate of a core if the temperature does not climb too high), fully buffered ECC DIMMS (which may require oversized heatsinks for reliable operation, according to Ars Technica), "QuickPath Interconnect" (a point-to-point interconnect that replaces the old front side bus technology), & many others.

Basically, all these posts that start with the premise that all it takes to get real benefits from the 64-bit kernel is a 64-bit CPU start with a flawed premise. It isn't just about wider data paths or addressing more memory. It is also about the details of how the CPU implements the 64 bit architecture (like internal bus speeds, cache sizes & levels, instruction set additions, & even more arcane stuff), how the system gets rid of heat, & much more.

It is a lot like saying that all V-8 engines are very much alike; therefore, they all are capable of developing 4000+ horsepower because some "Funny Car" class V-8 powered dragsters can, so there is no reason for car makers not to let us use more of that power latent in our V-8 powered family cars.

You can't use what isn't there.

You're right....
You should write it to Apple Marketing Dpt, most of their Ads campaigns try to hide it to 'basic' users and oversell the 64-bits wonderful world.... after buying people are disappointed and try yo understand why their computer is not 'so fast' as Apple mktg told it should be...
and.
they write posts in this forum ;-))

Apple isn't hiding anything about 64 bit computing. It is just that some users think they have found evidence of something that isn't there, like a miraculous software-based way to make all 64 bit hardware architectures equally powerful. 😟