Doesn't the two different kernels require separate drivers for both? That could get confusing with third parties. I thought the main difference between Leopard and Snow Leopard (as far as the OS architecture) was Leopard's 32 bit kernel since everything else is already 64 bit. I have a Penryn / Santa Rosa Macbook (4,1). Will it be fully 64 bit?
Quote:
Originally Posted by foo2
The supporting chipset need not be 64-bit in order to run 64-bit apps, but it is possibly required to run the 64-bit kernel. A 32-bit chipset just won't run 64-bit applications as fast as if a 64-bit chipset was present.
I believe a 64-bit EFI is also required to run the 64-bit kernel, but again the EFI doesn't matter for running 64-bit apps.
So... who knows of any Apple laptops that use a 64-bit EFI?
Quote:
Originally Posted by jazzguru
Can 64-bit apps run in a 32-bit kernel?
This is a big difference that some people confused about. Snow Leopard will be the first Mac OS X operating system that comes with 64-bit slices for its applications by default. Leopard supported running 64-bit applications but nobody took advantage of it (for many reasons, mainly because of Apple). If you have a Core 2-based Mac, or a Nehalem-based Mac Pro, your computer will run 64-bit applications natively. If you have an original Yonah (Core) Intel Mac/Mac mini, your computer will run 32-bit applications just as it did in Leopard.
Snow Leopard is also the first operating system to support a 64-bit kernel. However, no computer will boot into a 64-bot kernel by default except the 2008 and later Xserve machines. Only Core 2 machines that came out in mid-2008 and later are capable of booting into a 64-bit kernel. There are many requirements for booting into a 64-bit kernel including driver support, 64 bit EFI support and more.
However a 64-bit kernel is nothing to write home about. Mainly, it allows the kernel to address large amounts of RAM, but unless you have 32GB of RAM there's nothing to write home about. In some cases K64 will be faster, but in some cases it can be slower. The kernel is very sensitive to memory and depending on how much/little you have, K64 may be slower. They'll continue to fine tune it but they make no contention that K64 is not for the average user right now. In the future it will be important but for now, it won't buy you anything. It's mainly for the future.
Actually the wording implies that the 9400M is not the minimum requirement for H.264 acceleration, rather it is the only graphics chip supported. Which of course might lead to the weird circumstance where switching to the 9600M GT in the MacBook Pro means losing H.264 acceleration support.
When you switch graphics chips on a MBP, does it completely turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
Quote:
Hopefully, Apple expands H.264 acceleration since there is no reason to limit it to the 9400M only. The 8600M GT, 9600M GT, GT120, and other similar nVidia GPUs have the same PureVideo HD decoder. SImilarly, ATI chips since the HD2000 series have had full hardware H.264 acceleration support. What's more, even the ATI X1000 series and nVidia 7000 series in the original Intel Macs had partial H.264 hardware acceleration support that is enabled in Windows. It's really a matter of whether Apple will refuse to support it.
We don't know if it's Apple refusing or if there are certain technical hurdles. I know they aren't going to explain it though. A plausible alternate explanation is that OS X uses the graphics chip in a little bit different way than Windows does, and that limits the ability to access certain video hardware features such as video encoding and video deinterlacing. I really don't know which is true, though I really wish I had access to the hardware video deinterlacing features.
if the Up-To-Date program is limited to being within 90 days of purchase, and started June 8th, then Snow Leopard must be released by September 6th. Otherwise someone who purchased on June 8th wouldn't be eligible.
Yes they would. The "normal" up-to-date" program is within 90 days of purchase.
Snow Leopard up-to-date is "if you?ve purchased a qualifying computer or Xserve on or after June 8, 2009 that does not include Mac OS X Snow Leopard, you can upgrade to Mac OS X Snow Leopard for $9.95."
When you switch graphics chips on a MBP, does it turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
You've just gotta be right. The "nothing but 9400" interpretation violates the principle of least astonishment. It's not like they rushed this thing out. Snow Leopard has been cooking quite awhile.
PPC was as scalable, maybe more, but there was no interest.
Correct, Apple and IBM had no interest in establishing a higher-performance alternative platform. If they had, they would not have completely dropped the ball on CHRP. Yet another golden opportunity lost to Jobs' unrelenting need for 100% control over everything Apple does.
However a 64-bit kernel is nothing to write home about. Mainly, it allows the kernel to address large amounts of RAM, but unless you have 32GB of RAM there's nothing to write home about. In some cases K64 will be faster, but in some cases it can be slower. The kernel is very sensitive to memory and depending on how much/little you have, K64 may be slower. They'll continue to fine tune it but they make no contention that K64 is not for the average user right now. In the future it will be important but for now, it won't buy you anything. It's mainly for the future.
A 64-bit kernel is actually an important security feature. For one thing, the few viruses there are for OS X would presumably be written to exploit the 32-bit kernel and would break in a 64-bit OS X kernel. I believe this is certainly one major benefit in running 64-bit Windows over 32-bit Windows. What's more, advanced security features, specifically memory randomization is significantly more effective with a 64-bit kernel since the much larger virtual memory space, regardless of how much RAM you actually have, means addresses are actually random. 10.5 Leopard's current memory randomization implementation is not effective and this has been pointed out by Charlie Miller, famous for his Pwn2Own Mac winnings, as one of the reasons why he's able to hack OS X so quickly. The much maligned Vista by contrast, does have an effective memory randomization implementation, so on the surface is harder to hack although more people try of course. The 32-bit kernel in Snow Leopard will no doubt improve things, but shortchanging older Macs either because they don't want to write more 64-bit drivers or push out 64-bit EFI firmware updates does mean they are shortchanging end user security as well. It is really in Apple's best interest to keep their users as secure as possible since as Microsoft found, once your security reputation is compromised by a major active exploit, it's very difficult to reverse public opinion.
Quote:
Originally Posted by JeffDM
When you switch graphics chips on a MBP, does it turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
Personally, I'm hoping that Apple will find a way to optionally enabled both the 9400M and the 9600M GT to operate at the same time. SLI isn't really worthwhile for Apple to invest in since it requires custom driver profiles for every game and application to be effective. However, Apple could still make use of both GPUs by say using the 9400M for OpenCL accelerating a physics engine and the 9600M GT for the graphics pipeline in a game. You'd better be plugged in of course.
Personally, I'm hoping that Apple will find a way to optionally enabled both the 9400M and the 9600M GT to operate at the same time. SLI isn't really worthwhile for Apple to invest in since it requires custom driver profiles for every game and application to be effective. However, Apple could still make use of both GPUs by say using the 9400M for OpenCL accelerating a physics engine and the 9600M GT for the graphics pipeline in a game. You'd better be plugged in of course.
Me too, but they haven?t done it yet so it seems unlikely at this point. I wold have thought that you can set it up in Sys Prefs power savings to have the GPU or IGP on all the time, or have the GPU turn off when you go to battery. This just isn?t the case and yet Apple with their control of limited HW configurations and OS should have the easiest time of this process. To have you restart to make the switch take and not be able to use both the IGP and GPU in conjunction is definitely a miss for coolness of Snow Leopard.
Actually the wording implies that the 9400M is not the minimum requirement for H.264 acceleration, rather it is the only graphics chip supported. Which of course might lead to the weird circumstance where switching to the 9600M GT in the MacBook Pro means losing H.264 acceleration support. Hopefully, Apple expands H.264 acceleration since there is no reason to limit it to the 9400M only. The 8600M GT, 9600M GT, GT120, and other similar nVidia GPUs have the same PureVideo HD decoder. SImilarly, ATI chips since the HD2000 series have had full hardware H.264 acceleration support. What's more, even the ATI X1000 series and nVidia 7000 series in the original Intel Macs had partial H.264 hardware acceleration support that is enabled in Windows. It's really a matter of whether Apple will refuse to support it.
If you have a Core 2-based Mac, or a Nehalem-based Mac Pro, your computer will run 64-bit applications natively.
More accurately, absolutely all Mac Pros can run 64-bit applications ("natively" [sic]). This includes the original Wolfdale (August 2006), Clovertown, Harpertown (2008) and Nehalem (2009) Mac Pros. But only the Harpertown and Nehalem Mac Pros have 64-bit EFIs with which to support the Snow Leopard 64-bit kernel.
The question no one here seems to have answered thus far is: which (if any) MacBook Pros have a 64-bit EFI?
It would appear that for Snow Leopard to allow a 64-bit kernel three criteria must be met: 64-bit CPU, 64-bit chipset and 64-bit EFI.
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset (in laptops, Santa Rosa or newer).
The 9400M is part of the chipset, and is thus always running.
I wonder about that though, because power management techniques often mean that power and clock to unused portions of a chip are turned off. No sense in letting current drain needlessly.
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset.
The early 2008 models of the Mac Pro, 15" and 17" MacBook Pro and Xserve can be used for 64-bit kernel development. Audio and AirPort are now enabled on these on these testing configurations. In SnowLeopard, the 64-bit kernel is is used by default on the Xserve and the Mac Pro and MacBook Pro systems can be booted into the 64-bit kernel in one of two ways:
1) Temporarily boot into the 64-bit kernel by holding down "6" and "4" while powering on the machine
2) Run `sudo nvram boot-args="arch=x86_64" ` to set the 64-bit kernel as your default kernel, and append any other debugging flags you may need, such as "debug=0x144". To revert back to the 32-bit kernel as the default, you can run `sudo nvram -d boot-args`.
This seed contains the necessary support for porting kexts to 64-bit and developers are strongly encouraged to do so.
This might be a bit more authoritative, depending on whether you believe they accurately transcribed Apple's release notes. This is from an earlier developer seed so of course things could have changed, but basically 64-bit support looks to start from at least Macs with 45nm Penryns and up. (Harpertown being a Penryn derivative.)
Technically, Nehalem's are best for 64-bit support since Intel processors before Nehalem (Merom and Penryn) had macro-op fusion disabled in 64-bit mode meaning that they couldn't combine 2 instructions together an issue 5 instructions instead of 4. Intel estimated macro-op fusion could work with an average 10% of instructions that a processor received, which is probably very generous and not the same as a 10% performance boost anyways. Still, the raw potential performance of Merom and Penryn processors drops slightly in 64-bit mode compared to 32-bit mode. Other efficiencies in a 64-bit kernel code easily make up for this though.
I am still feeling that Apple's 64-bit kernel support should be as broad as possible, even for Macs that don't support 4GB+ of RAM, because of security reasons.
EDIT:
Reported seed notes from a more recent April 2009 developer build shows this:
Yeah hopefully, but not really. They can make their money elsewhere.
Even at full price, Apple's operating system is an insane value for the money. The fact that they optimized 90% of it and added huge new features and improvements and are only charging $29 is unbelievable. That's about 1/10th the price of Vista Home Premium crapware. They've had hundreds or even thousands of product managers, developers, researchers, QA people and senior management working on this for over a year.
How on Earth can anyone feel justified in STEALING this wonderfully-priced product that Apple put its blood, sweat and tears into?
Call my crazy, but I don't shoplift when I'm at the mall. I don't steal books from the library. I don't pocket money and jewelry when I'm at a friend's house. I don't steal money from my elderly parents. I don't steal my cable or my internet. I don't steal from the Salvation Army Santas or the donation bowl. I haven't dumped my obligations to my mortgage lender, cheated on my taxes or failed to pay the teenager who mows my lawn. And believe it or not, I don't steal music, or videos, or software. Maybe I'm just a "better" human being; I believe you shouldn't take what you haven't either earned, paid for or received as a gift. What the heck is wrong with people these days?
Ask yourselves this: How would you feel if someone stole something you put your blood, sweat and tears into? And please, don't say Apple can make their money elsewhere. So could you -- does that make it any less wrong when someone steals from you?
By the way, their operating system is a core revenue component. It's not like they do it for fun.
Yes, it's a big deal, since system function calls are much faster on 64 bit kernel.
All I can say is if 64 bit kernel is not supported on all 64 bit CPUs then they can take the Snow Leopard and shove it. It's a completely pointless stop gap update. Basically, re-purchase all your hardware when 10.7 comes out, and Mac will finally be 64 bit, full 12 years after Windows and Linux. What a shame.
12 years after Windows and Linux? That's a joke. Which versions of Windows and Linux did people buy 10 years ago?
I would not be surprised. It is well known fact in technical circles that entry level $50 ATI HD2600 card is beating $3000 nVidia Quadro 4800 in core animation benchmarks. And why? Because Apple doesn't know how to write the damn drivers and won't let nVidia do it.
Can you provide us with the information showing that Apple doesn't know how to write the drivers and isn't allowing Nvidia to do it?
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset (in laptops, Santa Rosa or newer).
This article from, of all places, AI, will answer some of these questions. It's in there, just read.
Comments
Doesn't the two different kernels require separate drivers for both? That could get confusing with third parties. I thought the main difference between Leopard and Snow Leopard (as far as the OS architecture) was Leopard's 32 bit kernel since everything else is already 64 bit. I have a Penryn / Santa Rosa Macbook (4,1). Will it be fully 64 bit?
The supporting chipset need not be 64-bit in order to run 64-bit apps, but it is possibly required to run the 64-bit kernel. A 32-bit chipset just won't run 64-bit applications as fast as if a 64-bit chipset was present.
I believe a 64-bit EFI is also required to run the 64-bit kernel, but again the EFI doesn't matter for running 64-bit apps.
So... who knows of any Apple laptops that use a 64-bit EFI?
Can 64-bit apps run in a 32-bit kernel?
This is a big difference that some people confused about. Snow Leopard will be the first Mac OS X operating system that comes with 64-bit slices for its applications by default. Leopard supported running 64-bit applications but nobody took advantage of it (for many reasons, mainly because of Apple). If you have a Core 2-based Mac, or a Nehalem-based Mac Pro, your computer will run 64-bit applications natively. If you have an original Yonah (Core) Intel Mac/Mac mini, your computer will run 32-bit applications just as it did in Leopard.
Snow Leopard is also the first operating system to support a 64-bit kernel. However, no computer will boot into a 64-bot kernel by default except the 2008 and later Xserve machines. Only Core 2 machines that came out in mid-2008 and later are capable of booting into a 64-bit kernel. There are many requirements for booting into a 64-bit kernel including driver support, 64 bit EFI support and more.
However a 64-bit kernel is nothing to write home about. Mainly, it allows the kernel to address large amounts of RAM, but unless you have 32GB of RAM there's nothing to write home about. In some cases K64 will be faster, but in some cases it can be slower. The kernel is very sensitive to memory and depending on how much/little you have, K64 may be slower. They'll continue to fine tune it but they make no contention that K64 is not for the average user right now. In the future it will be important but for now, it won't buy you anything. It's mainly for the future.
Yeah hopefully, but not really. They can make their money elsewhere.
Spoken like a tool.
Actually the wording implies that the 9400M is not the minimum requirement for H.264 acceleration, rather it is the only graphics chip supported. Which of course might lead to the weird circumstance where switching to the 9600M GT in the MacBook Pro means losing H.264 acceleration support.
When you switch graphics chips on a MBP, does it completely turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
Hopefully, Apple expands H.264 acceleration since there is no reason to limit it to the 9400M only. The 8600M GT, 9600M GT, GT120, and other similar nVidia GPUs have the same PureVideo HD decoder. SImilarly, ATI chips since the HD2000 series have had full hardware H.264 acceleration support. What's more, even the ATI X1000 series and nVidia 7000 series in the original Intel Macs had partial H.264 hardware acceleration support that is enabled in Windows. It's really a matter of whether Apple will refuse to support it.
http://www.apple.com/macosx/specs.html
We don't know if it's Apple refusing or if there are certain technical hurdles. I know they aren't going to explain it though. A plausible alternate explanation is that OS X uses the graphics chip in a little bit different way than Windows does, and that limits the ability to access certain video hardware features such as video encoding and video deinterlacing. I really don't know which is true, though I really wish I had access to the hardware video deinterlacing features.
Woohoo.....time to torrent when leaked!
What a dick...
That's what she said
But you only thought it was a compliment.
if the Up-To-Date program is limited to being within 90 days of purchase, and started June 8th, then Snow Leopard must be released by September 6th. Otherwise someone who purchased on June 8th wouldn't be eligible.
Yes they would. The "normal" up-to-date" program is within 90 days of purchase.
Snow Leopard up-to-date is "if you?ve purchased a qualifying computer or Xserve on or after June 8, 2009 that does not include Mac OS X Snow Leopard, you can upgrade to Mac OS X Snow Leopard for $9.95."
http://www.apple.com/macosx/uptodate/
When you switch graphics chips on a MBP, does it turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
You've just gotta be right. The "nothing but 9400" interpretation violates the principle of least astonishment. It's not like they rushed this thing out. Snow Leopard has been cooking quite awhile.
PPC was as scalable, maybe more, but there was no interest.
Correct, Apple and IBM had no interest in establishing a higher-performance alternative platform. If they had, they would not have completely dropped the ball on CHRP. Yet another golden opportunity lost to Jobs' unrelenting need for 100% control over everything Apple does.
However a 64-bit kernel is nothing to write home about. Mainly, it allows the kernel to address large amounts of RAM, but unless you have 32GB of RAM there's nothing to write home about. In some cases K64 will be faster, but in some cases it can be slower. The kernel is very sensitive to memory and depending on how much/little you have, K64 may be slower. They'll continue to fine tune it but they make no contention that K64 is not for the average user right now. In the future it will be important but for now, it won't buy you anything. It's mainly for the future.
A 64-bit kernel is actually an important security feature. For one thing, the few viruses there are for OS X would presumably be written to exploit the 32-bit kernel and would break in a 64-bit OS X kernel. I believe this is certainly one major benefit in running 64-bit Windows over 32-bit Windows. What's more, advanced security features, specifically memory randomization is significantly more effective with a 64-bit kernel since the much larger virtual memory space, regardless of how much RAM you actually have, means addresses are actually random. 10.5 Leopard's current memory randomization implementation is not effective and this has been pointed out by Charlie Miller, famous for his Pwn2Own Mac winnings, as one of the reasons why he's able to hack OS X so quickly. The much maligned Vista by contrast, does have an effective memory randomization implementation, so on the surface is harder to hack although more people try of course. The 32-bit kernel in Snow Leopard will no doubt improve things, but shortchanging older Macs either because they don't want to write more 64-bit drivers or push out 64-bit EFI firmware updates does mean they are shortchanging end user security as well. It is really in Apple's best interest to keep their users as secure as possible since as Microsoft found, once your security reputation is compromised by a major active exploit, it's very difficult to reverse public opinion.
When you switch graphics chips on a MBP, does it turn off the other chip? It would make sense. But doesn't the 9600 have the same encoding engine as the 9400? I'm thinking maybe it's just clumsy wording on the web site, we'll see.
Personally, I'm hoping that Apple will find a way to optionally enabled both the 9400M and the 9600M GT to operate at the same time. SLI isn't really worthwhile for Apple to invest in since it requires custom driver profiles for every game and application to be effective. However, Apple could still make use of both GPUs by say using the 9400M for OpenCL accelerating a physics engine and the 9600M GT for the graphics pipeline in a game. You'd better be plugged in of course.
Personally, I'm hoping that Apple will find a way to optionally enabled both the 9400M and the 9600M GT to operate at the same time. SLI isn't really worthwhile for Apple to invest in since it requires custom driver profiles for every game and application to be effective. However, Apple could still make use of both GPUs by say using the 9400M for OpenCL accelerating a physics engine and the 9600M GT for the graphics pipeline in a game. You'd better be plugged in of course.
Me too, but they haven?t done it yet so it seems unlikely at this point. I wold have thought that you can set it up in Sys Prefs power savings to have the GPU or IGP on all the time, or have the GPU turn off when you go to battery. This just isn?t the case and yet Apple with their control of limited HW configurations and OS should have the easiest time of this process. To have you restart to make the switch take and not be able to use both the IGP and GPU in conjunction is definitely a miss for coolness of Snow Leopard.
Actually the wording implies that the 9400M is not the minimum requirement for H.264 acceleration, rather it is the only graphics chip supported. Which of course might lead to the weird circumstance where switching to the 9600M GT in the MacBook Pro means losing H.264 acceleration support. Hopefully, Apple expands H.264 acceleration since there is no reason to limit it to the 9400M only. The 8600M GT, 9600M GT, GT120, and other similar nVidia GPUs have the same PureVideo HD decoder. SImilarly, ATI chips since the HD2000 series have had full hardware H.264 acceleration support. What's more, even the ATI X1000 series and nVidia 7000 series in the original Intel Macs had partial H.264 hardware acceleration support that is enabled in Windows. It's really a matter of whether Apple will refuse to support it.
http://www.apple.com/macosx/specs.html
The 9400M is part of the chipset, and is thus always running.
If you have a Core 2-based Mac, or a Nehalem-based Mac Pro, your computer will run 64-bit applications natively.
More accurately, absolutely all Mac Pros can run 64-bit applications ("natively" [sic]). This includes the original Wolfdale (August 2006), Clovertown, Harpertown (2008) and Nehalem (2009) Mac Pros. But only the Harpertown and Nehalem Mac Pros have 64-bit EFIs with which to support the Snow Leopard 64-bit kernel.
The question no one here seems to have answered thus far is: which (if any) MacBook Pros have a 64-bit EFI?
The question no one here seems to have answered thus far is: which (if any) MacBook Pros have a 64-bit EFI?
As convoluted as it is, your answer is in the link below?
http://refit.sourceforge.net/info/apple_efi.html
It would appear that for Snow Leopard to allow a 64-bit kernel three criteria must be met: 64-bit CPU, 64-bit chipset and 64-bit EFI.
As convoluted as it is, your answer is in the link below…
http://refit.sourceforge.net/info/apple_efi.html
It would appear that for Snow Leopard to allow a 64-bit kernel three criteria must be met: 64-bit CPU, 64-bit chipset and 64-bit EFI.
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset (in laptops, Santa Rosa or newer).
As convoluted as it is, your answer is in the link below…
http://refit.sourceforge.net/info/apple_efi.html
It would appear that for Snow Leopard to allow a 64-bit kernel three criteria must be met: 64-bit CPU, 64-bit chipset and 64-bit EFI.
I guess there's my answer. If EFI must be 64-bit, then my 2006 Mac Pro tower probably won't qualify unless Apple offers a firmware upgrade.
The 9400M is part of the chipset, and is thus always running.
I wonder about that though, because power management techniques often mean that power and clock to unused portions of a chip are turned off. No sense in letting current drain needlessly.
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset.
I posted this earlier.
http://news.worldofapple.com/archive...le-seed-notes/
64-bit Kernel
The early 2008 models of the Mac Pro, 15" and 17" MacBook Pro and Xserve can be used for 64-bit kernel development. Audio and AirPort are now enabled on these on these testing configurations. In SnowLeopard, the 64-bit kernel is is used by default on the Xserve and the Mac Pro and MacBook Pro systems can be booted into the 64-bit kernel in one of two ways:
1) Temporarily boot into the 64-bit kernel by holding down "6" and "4" while powering on the machine
2) Run `sudo nvram boot-args="arch=x86_64" ` to set the 64-bit kernel as your default kernel, and append any other debugging flags you may need, such as "debug=0x144". To revert back to the 32-bit kernel as the default, you can run `sudo nvram -d boot-args`.
This seed contains the necessary support for porting kexts to 64-bit and developers are strongly encouraged to do so.
This might be a bit more authoritative, depending on whether you believe they accurately transcribed Apple's release notes. This is from an earlier developer seed so of course things could have changed, but basically 64-bit support looks to start from at least Macs with 45nm Penryns and up. (Harpertown being a Penryn derivative.)
Technically, Nehalem's are best for 64-bit support since Intel processors before Nehalem (Merom and Penryn) had macro-op fusion disabled in 64-bit mode meaning that they couldn't combine 2 instructions together an issue 5 instructions instead of 4. Intel estimated macro-op fusion could work with an average 10% of instructions that a processor received, which is probably very generous and not the same as a 10% performance boost anyways. Still, the raw potential performance of Merom and Penryn processors drops slightly in 64-bit mode compared to 32-bit mode. Other efficiencies in a 64-bit kernel code easily make up for this though.
I am still feeling that Apple's 64-bit kernel support should be as broad as possible, even for Macs that don't support 4GB+ of RAM, because of security reasons.
EDIT:
Reported seed notes from a more recent April 2009 developer build shows this:
http://news.worldofapple.com/archive...rd-seed-notes/
Again, Penryn and up.
Yeah hopefully, but not really. They can make their money elsewhere.
Even at full price, Apple's operating system is an insane value for the money. The fact that they optimized 90% of it and added huge new features and improvements and are only charging $29 is unbelievable. That's about 1/10th the price of Vista Home Premium crapware. They've had hundreds or even thousands of product managers, developers, researchers, QA people and senior management working on this for over a year.
How on Earth can anyone feel justified in STEALING this wonderfully-priced product that Apple put its blood, sweat and tears into?
Call my crazy, but I don't shoplift when I'm at the mall. I don't steal books from the library. I don't pocket money and jewelry when I'm at a friend's house. I don't steal money from my elderly parents. I don't steal my cable or my internet. I don't steal from the Salvation Army Santas or the donation bowl. I haven't dumped my obligations to my mortgage lender, cheated on my taxes or failed to pay the teenager who mows my lawn. And believe it or not, I don't steal music, or videos, or software. Maybe I'm just a "better" human being; I believe you shouldn't take what you haven't either earned, paid for or received as a gift. What the heck is wrong with people these days?
Ask yourselves this: How would you feel if someone stole something you put your blood, sweat and tears into? And please, don't say Apple can make their money elsewhere. So could you -- does that make it any less wrong when someone steals from you?
By the way, their operating system is a core revenue component. It's not like they do it for fun.
Yes, it's a big deal, since system function calls are much faster on 64 bit kernel.
All I can say is if 64 bit kernel is not supported on all 64 bit CPUs then they can take the Snow Leopard and shove it. It's a completely pointless stop gap update. Basically, re-purchase all your hardware when 10.7 comes out, and Mac will finally be 64 bit, full 12 years after Windows and Linux. What a shame.
12 years after Windows and Linux? That's a joke. Which versions of Windows and Linux did people buy 10 years ago?
I would not be surprised. It is well known fact in technical circles that entry level $50 ATI HD2600 card is beating $3000 nVidia Quadro 4800 in core animation benchmarks. And why? Because Apple doesn't know how to write the damn drivers and won't let nVidia do it.
Can you provide us with the information showing that Apple doesn't know how to write the drivers and isn't allowing Nvidia to do it?
Yes, yes, yes, but which (if any) MacBook Pros have a 64-bit EFI? That question is still not answered, not even by that webpage (which doesn't appear to be authoritative anyway). FWIW: I have no doubt that if an Apple has a 64-bit EFI, it has a 64-bit microprocessor and a 64-bit chipset (in laptops, Santa Rosa or newer).
This article from, of all places, AI, will answer some of these questions. It's in there, just read.
http://www.appleinsider.com/articles...c_swindle.html