Hold 6 and 4 keys at boot to enable 64-bit Snow Leopard (Updated)
Summary: As I mentioned in a post last night, the latest developer release of Snow Leopard, a.k.
As I mentioned in a post last night, the latest developer release of Snow Leopard, a.k.a. Mac OS 10.6 (build 10A432, presumed to be GM) doesn't automatically boot into the 64-bit kernel except on an Xserve. To boot into 64-bit on any other Mac you must hold down the "6" and "4" keys at boot.
Update: There's a solution to the "64 finger salute" at the end of this post...
Here's how to tell if you've successfully loaded the 64-bit kernel in Snow Leopard:
- Launch System Profiler (Applications > Utilities > System Profiler or About This Mac > More Info...)
- Click on the "Software" heading in the left pane
- Check the "64-bit Kernel and Extensions" line for a Yes or a No.
This is what it looks like in 32-bit:
This is what it looks like when the 64-bit kernel and extensions are loaded:
As I posted yesterday, you can check to see if your Mac has the 64-bit EFI (required to load the 64-bit kernel) by entering the following command in Terminal:
ioreg -l -p IODeviceTree | grep firmware-abiAccording to Apple all system applications except DVD Player, Front Row, Grapher, and iTunes have been rewritten in 64-bit. All we need now is for third-party developers like Mozilla, Microsoft and Adobe (hint, hint!) to start releasing 64-bit apps :)
What applications do you want to go 64-bit first?
Update: If you're not a fan of having to remember to hold down the "6" and "4" keys each time you re-boot, there's a fix courtesy of Netkas.org:
Edit this file:
/Library/Preferences/SystemConfiguration/com.apple.Boot.plist<key>Kernel Flags</key> <string></string>
To this:
<key>Kernel Flags</key> <string>arch=x86_64</string>
Boots into the 64-bit kernel like a charm every time on my MBP.
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Talkback
Can you clarify this for me?
Can you confirm for me: do I need to hold the 6 and the 4 keys on bootup to run 64 bit Windows 7 on my MacBook Pro?
It probably has less to do with the computer itself
and trust, like Quark (which was very late to OS X) and Adobe (which
lagged with Intel support).
What would have made more sense would have been to put 32-bit apps
in a container, much like what happened back in the good old days of
Classic environment, and relatively similar to what WOWexec does with
16 bit apps in 32 bit Windows, or 32 bit apps in 64 bit Windows. Oh well.
Wowexec is just for 16-bit...
Anyways, the senior dev on the visual studio project recently wrote an article about the bigger issues with 64-bit.
It really doesn't matter if companies support it, the problem is hardware limitations presently, and the obscene lack of parallelism implemented in non-server code.
The thinking here is that when you build a 64-bit application, you start out in a hole due to current L cache limitations. You increase the memory allocation by orders but magnitude, but the L1-3 caches stay the same. You then use excess memory and processor speed to dig yourself out of that hole. This is irrelevant under nehalem architecture and to a lesser degree AMD processors, but it's still a factor. Most macs (and indeed pcs) don't run that platform yet, and it's not entirely out of the woods because a 64-bit floating point is HUGE. In fact, it's for all intents and purposes infinite. Running 32-bit apps in 64-bit mode allows you to gain the advantage of the memory address increase without taking the performance hit of 64-bit -> L1/2.
SSE instructions can help offset this, but only on hardware that supports it. Apple was an early SSE adopter, but you still run into the fact that at present, it's generally better to run applications in 32-bit emulation mode rather than 64-bit.
That is not to say, however, that they should default to 32 in the name of compatability. In the end though, it's really the devs decision.
This is a developer release
That's a good point
me too! ;) [n/t]
Yet Window 7RC should be perfect
Pardon My Slowness
I haven't really seen the correlation between Apple advocates and those who are seem to think that a Windows RC should be perfect. In my general experience, an RC should be pretty close to the final release, but nothing is perfect.
Some of us Apple users have made noise that the Win7 upgrades are too expensive, but you should consider that good news, because that means we have some interest in running (and do run) Windows OSes and would like to upgrade to the latest and greatest.
Slowness Pardoned
Like I said before I could be misreading the blog and to be honest it is worded to imply that there is huge potential for 32bit Apps not to work at all when booted into 64bit.
Microsoft has worked hard to earn its bad press
were really left out in the cold, because Microsoft's response to the
complaints was, "Buy the upgrade (DOS 5)."
On the other hand, remember the Atari ST? After the one week
learning curve, you just did things with your computer, and it tended
(and I did say "tended") to do things the way you would expect.
I have an MCSE, and the knowledge that comes with it really doesn't
answer the questions I need resolved. I had totally forgotten the
feeling of Atari ST computing until I got my family an iMac. Wow, the
feeling returns. I can do stuff with my computer again, and if it
doesn't work out right away, I can figure it out without having to go
online and read TechNet.
Now, with OS-X, I have to ask: would you rather have a toy operating
system like Windoze, or a really robust, military tough solution like
Unix?
"They're in a room with a penguin? Mr. Gates, your men are already
dead..."
=H^)
Am I reading this right?
32-bit compatible.
[i]To ensure simplicity and flexibility, Mac OS X still comes in one version that runs both 64-bit and 32-bit applications. So you don?t need to update everything on your system just to run a single 64-bit program. And new 64-bit applications work just fine with your existing printers, storage devices, and PCI cards.[/i]
Key word being: applications
what part of ...
How many problems did they have w/ 64-bit XP and Vista with compatibility?
Huh???
As far as applications go
How many Apple Fanatics or Linux Fanatics came in bashing Windows 7 RC because a few minor issues. I guess only time will tell how much trouble this causes but if the FINAL release is going to have its users hold down the 6 and 4 key to get into 64bit then it seems like Apple needs to get their act together don't ya think?
Bwahahah.... Stop it.... I'll get a cramp from laughing too hard!
That's a good one. You had me there for a moment ;)
I'm certainly no fanboy of any of the camps, I've been on a Windows or Dos desktop for more than 20 years and even written some desktop apps for MS Windows but [b]come on...[/b] Virtually none... Really?
In my experience, MS has never rolled out an OS upgrade without application troubles. Except maybe Win95 -> Win98.
odd
If everything would work just fine, why not make the default boot to support 64bit apps?
Doesn't really matter, as I'm sure 64bit app support will be the default when SL ships. It just seems like an odd thing to me.
Jason what about your Apple Developer Connection NDA??
Your information my not even be relevant to the final release.
Not GM...some stuff still not finished
Haha, what crap.
yeah...
BIOS set up...