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08/23/09
08/23/09
I'm guessing the kernal has nothing to do with bootcamping Windows, but again, I'm just curious if Apple has updated any of that in SL.
08/23/09
A few links on the subject:
[msdn.microsoft.com]
Why can MacOS X access more and 32-bit XP less? Well the difference comes down to different OS architectures and the way they approach things.
08/23/09
I use Word a whole lot. Can I force boot into 64-bit so I can run Word in 64-bit?
I ask this because, if my math is correct, 64 is twice as much as 32. Therefore, Word running in a 64-bit environment should allow me to write twice as fast. I just want to know if my writing will see a major speed boost from 64-bit processing.
I got Office running on my VAIO with Win7 (64-bit) but I didn't notice a big speed boost like being able to write twice as much in half the time. I figure its gotta be cuz M$ doesn't know how to program. When Apple does 64-bit, thats when the next-Generation will really begin.
08/23/09
08/23/09
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08/23/09
08/24/09
Probably you are an 32 bit person, my good sir.
08/24/09
That's like running a 64 bit version of a GameBoy game on a Playstation 3. The GameBoy game doesn't need all the bits of a Playstaion for it to run.
08/24/09
08/24/09
08/24/09
08/23/09
Also, 64-bit apps on a 32-bit kernel means you're have to perform some type of emulation or translation every time you access kernel mode. Fail. Basically you're emulating 64-bit because *everything* beside something simple like user-mode math goes through kernel - accessing every bit of memory, any file I/O, device I/O, graphics, thread scheduling, etc..
08/23/09
08/23/09
I get pageouts every once in a while. Stuff continually gets bigger.
All 64-bit is... is memory addressing. Win/Mac are not going to get any sort of speed bump with 64-bit because it doesn't change your clock cycles.
08/23/09
08/23/09
08/23/09
08/23/09
Mac OS is a 64 bit OS because (every machine) can run 64 bit apps, with 64bit virtual memory space.
08/23/09
08/23/09
08/23/09
08/23/09
08/23/09
In either case that's troll bait if I ever saw it.
08/23/09
When the kernel is running, the CPU is in "supervisor mode" and the way its running has no bearing on "user mode" like when your app is running.
The key thing is...if you are not capable of running an app in 64-bit address mode (16 exabytes) then you're stuck with each program having a direct memory space of 4GB (minus some for kernel memory mapping.
That's 4GB for EACH application...at the same time.
SO...you can have 2GB in your iMac, and have one 32-bit program using 4GB, and two more using 4GB, each. The trick is that Virtual Memory will be doing a lot of swapping. Swapping because your system RAM is not enough, and because you're running 3 big, fat apps.
In real-life most apps are not using a huge number of active "pages" but apps like photoshop will, every single operation.
So, Win32 fanboys need not rejoice, this has no practical bearing on regular users or power users.
[Key point] Snow Leopard is an OS that supports 64 bit apps natively.
This is really a non-news item.
08/22/09
Seriously?
No offense, I love apple but even I feel rather confused by this "clarification"...
Either it's 64 bit, or it's 64 bit sitting on top of 32 bit, which isn't true 64 bit. Which is it?
08/22/09
08/22/09
08/23/09
Mac users have traditionally had the ability to swap a hard drive from one Mac to another and expect it to run normally (obviously not between PPC and Intel), so it's reasonable for this to default to 32.
You can change it if you want.
08/22/09
08/22/09
08/22/09
Whatever. I don't really care about it. As long as it's faster, I'm happy. I just wish Apple would release Snow Leopard before school starts so I don't have to deal with the hassle of backing everything up and then switching OSes right is the middle of a bunch of school work.
08/22/09
08/22/09
08/22/09
ioreg -l -p IODeviceTree | grep firmware-abi
It will say either EFI32 or EFI64. EFI64 means you can use the 64-bit SL kernel.
08/22/09
Sorry about the multiple postings. I’m moving right now and I’m tethered with my iPhone and just jumped from 3G to EDGE to GPRS and back. Way to go AT&T! :D
08/22/09
I’m going to break this down because this should be really simple shit yet despite this having been discussed for months now, ad nauseam, Giz can’t even get it right.
— The ONLY systems that will default to a 64-bit kernel are the Xserves.
— ALL Macs will default to the 32-bit kernel.
— What Giz was reporting but got lost along the way is that even if you have a C2D or other 64-bit CPU you may not have an option to even launch with a 64-bit kernel, regardless if you use the 6-4 keys or use Terminal to edit the boot options.
Here is the list of "capable" Macs:
Note, that If your Mac has a model number newer than what is listed then you, too, will be able to boot using the 64-bit kernel.
— When you use a 64-bit kernel you then have to use 64-bit drivers.
—— This is why the Xserve, which will likely have no oddball or legacy peripherals connected to it default to the 64-bit kernel, though you can use the 32-bit kernel if there is a driver issue. ——Macs use a lot of different drivers from 3rd-parties for peripherals so it’s the user’s best interest to default to the 32-bit kernel.
— All the 64-bit drivers Apple is releasing are "universal" in that they are both 32-bti and 64-bit. Apple has been trying to get others to do the same.
— This was the expected result for the consumer HW since the initial announcement. Nothing ha changed!
— The only caveat is why don’t certain Macs have, at least, the option to load the 64-bit kernel. I have a 13" MBP with only the Nvidia 9400M and I can’t load the 64-bit kernel. Apparently it’s only for dual GPU MB/MBPs right now, despite me having a 64-bit CPU, 64-bit chipset and 64-bit EFI. (THE LACK OF THE OPTION IS THE ONLY MYSTERY!!!)
— 64-bit apps are the default and you can choose a 32-bit version of that app if you go into Get Info and check the box for 32-bit.
— 64-bit Safari 4.0.3 on Snow Leopard gets a 440ms on SunSpider, while 32-bit Safari 4.0.3 on Leopard does it in 880ms. In comparison a couple weeks ago Chromium was saying how it’s so much faster than Safari on Leoaprd with a 660ms score.
—— 64-bit kernel or apps does not automatically mean that apps will be faster, they may even be slower for certain tasks. This depends heavily on many factors that are too complex for this site and this already long post.
I hope that cleared some things up. Thank you and have a great weekend.
08/23/09