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Apple Hardware VP Defends Benchmarks

Greg Joswiak, vice president of hardware product marketing at Apple, in a phone interview today, defended Apple's performance claims for its upcoming Power Mac G5, after they came under fire in the wake of yesterday's announcement. Read on for the details. Joswiak went over the points in turn, but first said that they set out from the beginning to do a fair and even comparison, which is why they used an independent lab and provided full disclosure of the methods used in the tests, which would be "a silly way to do things" if Apple were intending to be deceptive.

He said Veritest used gcc for both platforms, instead of Intel's compiler, simply because the benchmarks measure two things at the same time: compiler, and hardware. To test the hardware alone, you must normalize the compiler out of the equation -- using the same version and similar settings -- and, if anything, Joswiak said, gcc has been available on the Intel platform for a lot longer and is more optimized for Intel than for PowerPC.

He conceded readily that the Dell numbers would be higher with the Intel compiler, but that the Apple numbers could be higher with a different compiler too.

Joswiak added that in the Intel modifications for the tests, they chose the option that provided higher scores for the Intel machine, not lower. The scores were higher under Linux than under Windows, and in the rate test, the scores were higher with hyperthreading disabled than enabled. He also said they would be happy to do the tests on Windows and with hyperthreading enabled, if people wanted it, as it would only make the G5 look better.

In the G5 modifications, they were made because shipping systems will have those options available. For example, memory read bypass was turned on, for even though it is not on by default in the tested prototypes, it will be on by default for the shipping systems. Software-based prefetching was turned off and a high-performance malloc was used because those options will be available on the shipping systems (Joswiak did not know whether this malloc, which is faster but less memory efficient, will be the default in the shipping systems).

As to not using SSE2, Joswiak said they enabled the correct flags for it, as documented on the gcc web site, so that SSE2 was enabled (the Veritest report lists the options used for each test, which appears to include the appropriate flags).

11 of 1,081 comments (clear)

  1. Re:Curious by pudge · · Score: 5, Informative

    Eh, we do this sometimes, when it is appropriate. In this case, I have a PR contact at Apple who asked me last week if I wanted to talk to someone about WWDC, and we set up a call last weekend, for this afternoon. It just happened to coincide with the benchmark discussion, which Greg was eager to set straight (he had read the arguments and already compiled his responses :-). We also talked a bit about some other topics, but nothing of interest that you haven't read elsewhere.

  2. Re:Benchmarks by j3ffy · · Score: 5, Informative
    But what was even more inpressive than the spec scores was watching the powermac squash the dual xeon in several applications from 3D video rendering, to photo editing, to audio processing, to mathematical calculations.

    I'm a science guy, and for the calculations and simulations done here at the physics dept. where I work, the IBM power4 kills just about everything else. And when I saw the powermac calculate fractals with mathematica faster than the xeon box by more than a factor of 2, I was very excited (although a little cautiously) to see we will soon get power4 performance for well under $20,000

  3. Re:But he didn't refute the most damning claim! by doce · · Score: 5, Informative

    this is the funniest claim i've seen in a while. not only does apple do this, so does dell, and so does virtually every consumer-oriented company on the planet. gas companies shave a TENTH of a PENNY off gas prices to make them seem cheaper.

    a department store (was it macy's?) started this practice. the funny part is that the aim wasn't really to fool consumers into thinking it was less expensive. alas, the real purpose was to force cashiers to open the register, since the customer was almost always going to be due some change.

    --
    woof!
  4. Reasonable claims - IBM's Power4 vs Intel by slyfox · · Score: 4, Informative
    Apples claims seem quite reasonable to me. Why? Look at the other reported SPEC scores for Power4+ (the G5/970 is based directly on IBM's Power4+ processor core). Right now the Power4 ranks well on both SPECint2000 and SPECfp2000. See the SPECfp2000 and SPECint2000 benchmark report summaries.

    SPECfp: The Power4+ at 1.7 Ghz has the highest SPECfp score (1699 @ 1.7Ghz); higher than Itanium (1431 @ 1Ghz), the most recent Alpha (1482 @ 1.15Ghz), and the Pentium 4 (1229 @ 3.0Ghz).

    SPECint: As far as SPECint, the Power4 is not in the lead (1113 @ 1.7Ghz), but is still respectable when compared to Pentium4's (1200 @ 3.0Ghz).

    The G5/970 should do similarly or better than the G5/970 (since the G5/970 is running at 2.0Ghz vs Power4+ 1.7Ghz). One caveat is that the G5/970 has a smaller on-chip second-level cache (512kB vs 1.5MB), which will hurt its performance on some codes.

    Certainly Apple's test uses a drastically different compiler than the reported SPEC results. This results in absolute numbers that are lower, but Apple's relative comparison is still reasonable, IMHO. I think it is safe to claim that Apple has really closed the gap in processor speed and now has processors with comparable performance to the fastest chips money can buy. About damn time. :)

  5. Re:Apple: innovation or catch up? by tuxedobob · · Score: 5, Informative

    I don't think anyone's really arguing that most of Apple's improvements weren't catch up. Heck, when Steve Jobs was on stage he was saying how everything they added was "the latest PC standard". How could it not be catching up if it's already a standard on the PC?

    The reason the Mac users are happy about all this is because we already knew we were way behind, and we've been begging Apple to catch up!

    Even considering all the benchmarks, which may or may not be accurate, the simple fact remains that this Mac is much faster than the previous Mac. Which is good news for Mac users. And presumably the crowd at the keynote was full of Mac users.

  6. Re:Who cares? by RestiffBard · · Score: 4, Informative

    you know this and I know this but many trolls don't know this. I think Apple just got tired of hearing how PCs are faster and what not. Personally I was blown away by the keynote. Also, for anyone wondering I'm using the developer preview now and if the release of Panther is anything like the preview, holy crap. It is nice. There are a ton of tiny improvements here and there that really make it nice, even nicer than Jaguar. These are little things that weren't mentioned in the keynote.

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    - /* dead coders leave no comments */
  7. Re:Removed one of the processors for the SPEC CPU by dhovis · · Score: 4, Informative

    Actually, I just watched the video again. He actually said:

    We wanted to find a test that used 6GB of memory, but we couldn't find one that didn't destroy the Xeon. It would have been thrashing about for a week.
    --

    --
    The internet is the greatest source of biased information in the history of mankind.

  8. Re:Other Benchmarks? by Anonymous Coward · · Score: 4, Informative

    The Apple Quake 3 benchmarks disabled hardware acceleration. They were solely testing the CPU, or trying to at least. The guy from... oh, damn, what's that guy's name, the guy who did the OpenGL demo yesterday. He did the same thing. They did all the rendering they could in the CPU.

    That's why the numbers were low compared to other tests that used accelerated graphics.

  9. More on benchmarking by kajod_kaka · · Score: 4, Informative

    The 30th International Symposium on Computer Architecture had an interesting panel discussion on benchmarking in industry and academia, with people like John Hennessy, Dave Patterson and Gurinder Sohi on stage. The conclusions: most benchmarking in industry, especially SPEC, is a pack of lies. And benchmark results published by academic researchers aren't much better. So, not really much point in losing a lot of sleep at least over their SPEC numbers.

  10. Re:Who cares? by Computer! · · Score: 4, Informative

    I just got a 450MHz G4 Cube (pre-owned, obviously).

    I have used high-end workstation-class machines, both RISC and CISC, multi-GHz Intel machines, and Macs back to System 6. This Cube is without a doubt the best computer I have ever owned or used.

    That having been said, I have seen Apple make some prety serious hardware and customer service mistakes. I would buy another Mac in a heartbeat, but I would wait for these systems to ship for at least six months before buying one of them. Wait until you can check Mac help forums. Find out what the problems are, if any. You don't want to spend $3000 on a computer, and have the paint chip off.

    --
    If you fall off a building, go real limp, because maybe you'll look like a dummy and people will be like hey, free dummy
  11. Photoshop WAS compiled with the AIX compiler! by kriegsman · · Score: 5, Informative
    I don't know if they still do, but for a while at the beginning of the PowerPC era Adobe was using the AIX compiler to generate its PowerPC binaries for Photoshop.

    Admittedly, this was when the PowerPC was pretty new, and the choices were the IBM/AIX compiler which was robust and produced fast code but required an AIX box in addition to a Power Mac, or the nacent Metrowerks CodeWarrior compiler which run natively on the Power Mac, but generated poorly optimized code.

    If I recall my history timeline correctly, after CodeWarrior came
    • the Apple MPW "MrC" compiler (better code than CodeWarrior 1.0, but with a wacky command-line "IDE"), then
    • gcc for PowerPC (cruddy code back then), then
    • the Motorola PowerPC compiler (better code than Apple's compiler, with NO IDE - it plugged into the CodeWarrior or MPW IDE).
    • Then Motorola inexplicably stopped selling their compiler.
    • Later Motorola bought Metrowerks.
    • Somewhere along the line, gcc learned to generate better PowerPC code.
    • Eventually, Apple pretty much shelved their "MrC" compiler, and settled on using gcc for Mac OS X
    • Monday, Apple released their "Xcode" environment -- still using gcc, I believe.
    Apple's MPW tools are still available (free) here for Mac OS 7/8/9. The new Mac OS X tools including Xcode are available here.

    As a side note, it's really nice to see Apple giving away a full development suite for free, and continuing to put development time and effort into improving it.

    -Mark