Questions about OSX and PPC 970

The processor should run fine in 32-bit mode, though you'll still be stuck with the file system and memory limits we currently have.

Immediately for power users, the improved/updated file system should allow them a rather large HD. Not to mention access to memory far beyond the current 2-4GB limit.

The real benefits will be the updated bus and I/O, which will speed up operations much more than anything else.

The 970 has one extra Floating Point Unit, so it will be a bit faster than the G4s in this area.

You'll alway have companies that take awhile to make the transition (ie Quark).

And it's a little hard to say what 32-bit mode would be, since you have the old file systems to support, classic Applications, and even the current Cocoa Applications.

OS X will have to be updated to provide 64-bit support, but the current 32-bit version should run fine after it is given the necessary 0.x upgrade to support the updated architecture. Just like a new PowerBook today won't run the old OS 8, but a PowerBook from a few years ago will run whatever the newest OS is.

64-bit OS X

Originally posted by arn
Mac OS X will have to be rewritten to run on PPC 970, but apps should run fine without having to be rewritten.

arn

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Not rewritten. Simply, OS X needs to be recompiled using new compiler that supports everything 64-bit: instructions, function calls, memory mapping & addressing and everything else.

Observing the modular architecture of the Mac OS X, and how wisely it was constructed, this can be done anytime. OS X is 64-bit ready and it was designed to be a 64-bit operating system.

In 10 to 12 years from now, 128-bit operating systems (inless they invent QC) will be in fashion, so expect 64-bit processors and 64-bit operating systems to rule the Earth during the next decade.

Re: Re: 64-bit OS X

Originally posted by arn


well, not rewritten... though I think there may be slightly more modification req than recompliing...but I don't know details... that was just my impression.

arn

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In *theory*, if apple has been crossing its t's and dotting its i's (not assuming integer sizes, typedefing everything) it should just be a recompile. Of course, no big complex system is perfect, so likely there will be some tweaks necessary, but it is clear that Apple is putting a big focus on keeping as much of the OS hardware independent as possible (Darwin on x86). I would bet that a 64 bit version of OSX is running in Cupertino as we type, on a 970-based machine, with a 64-bit clean version of Photoshop and Final Cut running on it.

The only question is when. So what's up Arn? I haven't heard *anything* about the 970 from rumors sites lately, other than macosrumors occasional lunatic ravings. What are your sources saying?

I really, really hope that IBM adopts a normal Roadmap system for the 970, so that we can make normal purchasing decisions, rather than the current ear-to-the-ground-oh-****-I-bought-before-a-release system that Apple currently employs.

Cheers,
prat

I have a practical question. I do a lot of audio work, and audio apps rely heavily on FPUs as well as altivec.

What sort of benefits would audio software get, if compiled and written properly, from the 970?

Most people only talk about the implications of it on graphics software, but realtime audio is just as stressful, if not moreso.

Re: Re: Re: 64-bit OS X

Originally posted by praetorian_x
In *theory*, if apple has been crossing its t's and dotting its i's (not assuming integer sizes, typedefing everything) it should just be a recompile.

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That should be true for everything in OS X except for the kernel. No matter how hard you try, going from one processor architecture to another one is never a simple recompile.

My guess though is the major work to get OS X running on a PowerPC 970 is not the 32-bit versus 64-bit part but the new processor and hardware architecture part. Since OS X is based upon pretty portable components, I would imagine once they got the kernel running on the sample CPUs and motherboards, the rest is a cake walk by comparison.

If Apple did things right, then applications which already run under 64-bit UNIXes, like Oracle, should have a very smooth transition.

Originally posted by Ajmbc
Also, does anyone have any cool names for the 970??

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Anybody notice that if you type "970" on a calculator and turn it over it says "Old"?

Oops it says "olb". Never mind.

Originally posted by arn
Mac OS X will have to be rewritten to run on PPC 970, but apps should run fine without having to be rewritten.

arn

Click to expand...

Actually from reading the various articles on the net, apparently some modifications will have to be done to the kernel for processor specific functions. Other then that, the 32 bit code will run fine on the 970.

I suspect the road map for 970 support will run like:

• Release a 970 based Mac with OS X updated. This will be all 32 bit mode.
• Release a version of OS X that runs in full 64 bit mode. Some applications will have a 64 bit version, but not all. This won't matter since 32 bit applications should still run fine.
• Applications will over time have 64 bit releases. Especially the "professional" applications.

Sun Solaris runs 32 or 64 bit applications fine on the UltraSPARC processors (64-bit).
The first two generations of the UltraSPARC could run either the 32 or 64 bit version of the OS. The third generation requires the 64-bit OS, but can still run 32 bit applications fine.

There is no reason that Apple shouldn't follow much the same with the 970 chips. This makes it an easier transition for everybody involved.

Bear:

Most apps will probably get slower in 64-bit mode so I do not expect most to transition. 64-bitness is almost useless other than the extra memory addressability.

springscansing:

The 970 should be a lot faster than a G4 (even at the same clock speed) for just about any task you can think of. It will gain a huge amount in heavy double-precision floating point code. There may also be a few rare cases where it looses ground (at the same clock) because it has a smaller total chip cache (no L3), but I think those cases will be very hard to find.

Re: Re: Re: Re: 64-bit OS X

Originally posted by ktlx


That should be true for everything in OS X except for the kernel. No matter how hard you try, going from one processor architecture to another one is never a simple recompile.
...

If Apple did things right, then applications which already run under 64-bit UNIXes, like Oracle, should have a very smooth transition.

Click to expand...

Right, but I thought that the strategy with the Mach kernel was to get as much code into hardware neutral space as possible. If porting it to x86 is possible, then a 64 bit PPC processor will be cake (comparatively).

The window manager code may be a bit more of a b**ch, but I would imagine that most of the optimizations are altivec'd (which the 970 supports), and with QE, so they are pushed off to the GPU.

So, yeah, I was being flippant in saying that it should just be a recompile. But it shouldn't be *that* much work.

Cheers,
prat

IBM has officially stated that a few minor modifications will be required for 32 bit operating systems to run on the 970. If Apple's at all intelligent, those have already been done.

Of course there's always the chance Apple won't use these CPUs.

i_b_joshua

Originally posted by i_b_joshua
Of course there's always the chance Apple won't use these CPUs.

i_b_joshua

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A pox upon you for suggesting so!

Cheers,
prat

Originally posted by i_b_joshua
Of course there's always the chance Apple won't use these CPUs.

i_b_joshua

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If they don't, they have SERIOUS problems. What else are they going to use? The 7457-RM doesn't come out until 2004 and would still be weak in FP and poorly optimized code (although a dual 7457-RM would be a monster of an Altivec machine). I suppose there's always the ISA switch option (x86-64, to bring back an over used option), but I think it would be insane to go to that much effort when the 970 should do just fine. Not using the 970 is possible, but I don't think it's likely.

Originally posted by Catfish_Man


If they don't, they have SERIOUS problems. What else are they going to use? The 7457-RM doesn't come out until 2004 and would still be weak in FP and poorly optimized code (although a dual 7457-RM would be a monster of an Altivec machine). I suppose there's always the ISA switch option (x86-64, to bring back an over used option), but I think it would be insane to go to that much effort when the 970 should do just fine. Not using the 970 is possible, but I don't think it's likely.

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Just playing devil's advocate. All that noise about AMD a few months back may not have been a red herring.

I'd prefer to see Apple work with the old giant though.

i_b_joshua