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More on the PowerPC 970
functor writes "Ars Technica's Jon Stokes has a treatise up covering the microarchitecture of the high-performance 64-bit PowerPC 970 microprocessor, due to be released by the end of the year, that goes over in detail how this chip is put together, and how we can expect it to perform. This is the follow-up to Stokes' article detailing the PPC 970's design philosophy. 'It appears to hold quite a bit of promise in bolstering Apple's currently almost obsolescent product line, and it appears to have been designed explictly to fulfil Apple's requirements. To say the least, the second half of this year looks to be pretty interesting as Apple's product line promises to become competitive performance-wise with IA-32 and x86-64-based PCs again.''
This implies that the decision of how much bus bandwidth to give the G4e was up to Apple - which it was not. Motorola designed the processor (for Cisco, depending on who you believe), and Apple made do with the anemic MaxBus at 133mhz that they got from Motorola.
Apple'd be putting DDR400 on the G4 right now if they could. None of this (well, except the decision to go Moto) was their fault.
Why this had to be posted the morning before my presentation to my supervizor is a clear indication that the universe is against me.
Time to hide my network cable until the end of the day.
___
Cogito cogito, ergo cogito sum.
Who knows whether it will still be competitive in several months when they actually want to offer it.
On the other hand Apple users won't have much of a choice, and neither has Apple.
The PPC 970 will not really make the Macintosh competitive with modern PC's. It will make it competitive with PC's from the beginning of this year, which are not the fastest available any more, and will be even slower when compared to the machines that are available when the PPC 970 ships, which is the very earliest that Apple machines based on it can ship. It will however go a long way to catching up, and take off a lot of the pressure caused by the abominable performance of today's dual processor G4 machines when compared to even inexpensive PC's.
The other unkown in this is the price. PPC 970 based Apple computers may be significantly more expensive. Motorola loses hundreds of millions of dollars each year on their semiconductor business, and IBM does as well. Still, IBM may want to look at Apple and the PPC 970 as a PROFIT center, rather than a LOSS center, like Motorola does with Apple and the G4.
The PPC 970 is great news for Apple, but it is still a bone thrown to them while the x86 PC is feasting on the meat of the Intel and AMD processors.
Yeah, yeah, they are hog-tied because you can't easily re-compile the entire windows platform to use new instruction sets. Linux users, of course, don't have this problem (muhahahah).
Did anyone else catch the bit on the twin FPU's? I'm just imagining what this thing is going to do with vector operations and frequency transforms.
For most of you non-engineers:
Most 3d vector operations are affine tranformations. Using a 4x4 array of floating point numbers you can translate, rotate, and scale. Works beautifully, but it's a lot of calculations.
The Fast Fourier Transform (FFT) is used a lot in signal processing. It's a floating point monster.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
This is still a PPC chip. No changes to programs are necessary for them to run on it. The only change that will have to be made is if a software vendor decides to run in 64-bit mode which many don't have to do. Performance of the new chip is not dependent on whether the program runs at 32 or 64 bits. This is not a migration like moving from the 680x0 line of processors to the PPC which was an overall change in architecture.
Most users of Macs are in the graphics industry. Having BEEN there, I can tell you the 68k to PPC transition was a non-issue. The PPC ran the 68k code as fast as the old machines. The real transition was in restructuring applications, since they no longer needed to work around the brain-deadedness of the 68k series. Again, old apps were not affected.
The other point I would like to make is that they HAVE taken a page out of the GNU/Linux BSD page. MacOSX is an alternative window manager sitting on top of BSD!
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
Target multiple architectures. Let the users decide!
Y'know, I don't know why this keeps coming up. Apple's bottom line has always depended on keeping tight control over the hardware to allow maximum integration with their own software. And it works.
Keep in mind that Linux and BSD aren't targetted towards consumers who want to just "rip, mix, burn" or have plug-and-play that's actually exactly that. Even Windows can't deliver consistently on its promise of universal ease-of-use because so many vendors have so much hardware that may or may not work with the system and its existing drivers.
Whatever else you think about Apple's computers, they are without a doubt the easiest PCs on the planet if you're a neophyte. Take it from me, I've got two young women in my home who are all but completely computer-illiterate, and if I didn't have Mac OS X running they'd be constantly lost at sea. I'd love to try hooking up a Linux box for either or both of them, but there's no way I could expect them to use it. Macs are easy, and their users like them that way.
Yeah, I know it's a profit issue for Apple as well, because without business software sales like Microsoft relies on they'd be bankrupt without hardware profits. But I like to think it's more than just money. Apple cares about making a good and easy-to-use product, or else they'd just be chasing Windows like (sorry, not trolling here, but it's true) GNOME and KDE are instead of constantly innovating their own hardware and interface designs.
Targetting multiple architectures means that Apple's got to deal with unpredictable hardware configurations, cards, motherboards, drivers, all sorts of things that could cause inconvenient kernel panics, drive failures, or worse. Users are used to that with Windows, and they pretty much expect it with Linux. With Macs, they expect things to just work. Controlling the hardware is the best way for Apple to do that.
Lately many things have happened to apple, and if you take a brief look at thir lineup of both computers and gadgets you'll find that they are not dependent on anyone the same way they depended on motorola.
The music industry for iMS, AMD for the chips in the airport base station (and the iPod(?) don't know), Motorola for the non-pro lineup (iMacG4, iBook and the portables until they get 970), etc. etc.
I think Apple will go a long way to make sure they don't get stuck with one provider.
Also I think they are trying to be more competitive pricewise. By having a steady stream of income from selling iPods and songs via iMS, they get more money to develop hardware and software, and we just might get Powermacs970 below the $3k mark.
Be like the twenty-second elephant with heated value in space-Bark!
An interesting troll. An enjoyably subtle introductory paragraph, with only a hint of flamebaiting with the 'XP/Unix' comment. This trend is continued with the C/C++/C# evolution stanza, with its clean upfront palate, but lingering pleasant aftertaste. However, the trollish aromas start to become overpowering a little too soon with the sudden transition to assembly advocacy. A mature, well rounded troll will usually lead the reader through a gentler, more meandering path before delivering the closing fruity punch. Perhaps with a few years of cellaring, this troll may rank with such classics as the 1999 'BSD is dying' and the memorable 2000 'VB Programmer for a Fortune 500 company'.
All in all, not a bad effort for a beginner. 7/10.
Interesting, if you look at the pipeline design of the PowerPC it is much closer to Intel than AMD. The PowerPC pipeline has sixteen stages, the Pentium 4 twenty, and the Athlon ten.
Presumably the P4 can reach higher clock speeds than the Athlon because there is less work to do at each pipeline stage. On the other hand a longer pipeline increases the probability of a stall, so the work done per clock cycle goes down.
I'd speculate that the PowerPC ought, therefore, to be able to achieve clock rates approaching but not equalling the P4, since they are both comparatively "over-pipelined". At the same time, the PowerPC ought to deliver slightly more throughput per clock cycle because the pipeline is slightly shorter.
Meanwhile, the Athlon will be running at a significantly lower clock rate, but delivering comparable throughput.
Let's see....
You've got Job(s) in both.
History of being a persecuted minority.
Use of an Apple to gain more knowledge in both.
Christianity? Isaac. Apple? Imac.
Christianity? Prophets. Apple? Profits.
Don't blame Durga. I voted for Centauri.
It's not just AMD clocking lower either. The Itanium 2 isn't clocked that fast. Given that 32 POWER 4 1.7GHz processors smoked the 64 Itanium2 1.3GHz processors configuration in the latest TPCC non-clustered benchmark, the POWER and PPC architecture is capable of putting a lot more work through in the same number of clock cycles. There are a lot of nay-sayers trotting out the GHz-is-god line and it is particularly misleading for 64 bit architectures.
Cheers,
Toby Haynes
P.S. Disclaimer - I work in SOFTWARE for IBM, not hardware.
Anything I post is strictly my own thoughts and doesn't necessarily have anything to do with the opinions of IBM.
I'm sorry, but I don't see anything even approaching obsolete in Apple's product line.
NetInfo connection failed for server 127.0.0.1/local
The Pentium 4 is, in fact, designed to scale to high clock speeds exactly so that it can tolerate lots of pipeline bubbles in flight without ending up stalling for too long.
A lot of these tricks (high decode bandwidth, multiple instruction queues [really buffers meant for reordering the instruction stream], branch prediction, etc.) are meant to reduce hazards such as pipeline bubbles as far as possible, and the PPC 970 does these hazard-reducing operations rather well, too.
And, yes, we're now in the post-RISC world where instruction complexity (particularly in the realm of SIMD and streaming/explicit cache manipulation instructions) is growing because simple instructions clearly aren't enough to allow for great throughput increments.
(Read some of Stokes' older articles in the Ars Technopaedia; I'm sure you'll find them interesting.)
No. And I still don't think that's the reason. How can you make a word processor better using 64 bit code instead of 32 bit code? A spreadsheet? A web browser? An email client? A terminal emulator? A shell? A pdf viewer? I stand by my original point that most consumer apps don't need 64 bit operations.
I anticipated your short sighted response as soon as I hit the submit button. I should have realized that you would think I was talking about optimizing existing applications rather than designing new ones for new problems and I should have said all the rest of this stuff the first time... I even had a horrific vision of the word processor analogy. It was scary. Anyway:
I'm not talking about optimizing existing applications, I'm talking about new applications; programs that do things that we don't use our PCs for now. When we had 8-bit PCs nobody did photo editing or full color page layout on a PC. When we had 16-bit machines nobody used a PC for CAD. Now we have 32-bit machines and are moving to 64-bit. There will be some major tasks that will become possible with 64-bit PCs, but the software isn't there yet because the customers don't have the processors.
Also, I can think of two applications that every single computer user runs that can benefit dramatically from 64-bits, and Microsoft is waiting with the code already written for widespread 64-bit processor deployment to release them: Operating systems and filesystems. Having a 64-bit virtual address space can make your OS much more elegant and efficient since every possible I/O operation can be memory-mapped at once. Similarly, it has already been demonstrated that large relational databases benefit from 64-bit addressing even without taking advantage of the additional memory capacity, and many next generation filesystems will be relational databases.
Sure current consumer apps don't really need 64-bits. If they did we wouldn't have them. It's the PC apps of tomorrow that will benefit. If you don't care to do more with your PC then essentially what you can do today, just more quickly then keep buying 32-bit CPUs. They'll continue to be available for decades...
I manage labs of macs, totaling over 300 of them. The users of my labs have no complaints about performance. (They usually only start to whine when the find out the processor speed, but then they are conditioned to think that MHz is MHz; and when asked if their work is slowed, compared to what they do on a PC, they answer "no" it is not slower.)
:-)
What is this every non-mac user keeps saying that their performace is out of line with PC's? I have on my desk a hepped up dual P4 and a hepped up dual G4. XP on the dual P4 does not "feel," in day-to-day operations with standard apps like Office or Photoshop, much different from the dual G4. Comparing the MHz does not tell me anything. Using both side-by-side tells me a more "real" story about things. Now, perhaps XP is significantly slowing things down?
I only notice a difference with some high-end 3D apps like Maya or Lightwave, *maybe* also with some high-ed vid apps like Avid's.
I am looking forward to the 970 though. Actually, I am very curious about any 64bit CPU. Hopefully the "growing pains" for anyone to move to 64bit is negligible.