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NASA Benchmarks the New G5 Powermac

sockit2me9000 writes "Well NASA's Langley Research Center recently benchmarked the new G5 dual 2ghz Powermac against a dual 1ghz Xserve, a dual 1.25 ghz Powermac, a Pentium4 2 ghz, and a Pentium4 2.66 ghz. To make things fair, the second processor in the G5 was switched off, as well as the other dual sysytems. Then, they all ran Jet3d. Even with un-optimized code and one processor, the G5 performance is impressive."

23 of 751 comments (clear)

  1. Single Processor Mode by CptChipJew · · Score: 5, Informative

    Because I have a strong feeling this is going to be asked:

    For those of you who were wondering, you too can switch off one of your Mac's dual CPU's with the Apple CHUD Tools. Look near the bottom of the page. It'll make you appreciate your second processor ;)

    Personally though, I want to see how well it runs Seti@Home.

    --
    Vonal Declosion
    1. Re:Single Processor Mode by jbm · · Score: 5, Informative

      you ... can switch off one of your Mac's dual CPU's with the Apple CHUD Tools.

      You can also do this simply with the cpus= boot argument; here's a reference.
    2. Re:Single Processor Mode by furballphat · · Score: 5, Informative

      You only get the CPU tab if you install the CHUD tools, so you'll have to install no matter what.

  2. NASA Verifies Apple Benchmarks? by Dak+RIT · · Score: 5, Interesting
    Though dual processor benchmarks are not presented in detail here, it is worth noting that the G5 system benchmarked at 498 MFLOPS and 0.125 MFLOPS/MHz for scalar Jet3D performance when two processors were used.

    By adding a second processor, the MFLOPS/Mhz output only dropped from 0.127 to 0.125 MFLOPS/Mhz. This chip can definitely perform in a multi-processor environment. The P4 scored 0.096 MFLOPS/MHz with a single processor.

    Apple's benchmarks which were highly criticized by some, gave the Dual 2GHz Power Mac G5 a 194.5% performance advantage over a 3GHz P4 in SPECfp_rate_base2000. The G5 getting a score of 15.7, and the P4 getting an 8.07.

    NASA's study found the Dual 2GHz Power Mac G5 to score 498 MFLOPS for their Jet3D performance. A P4 running at 2.66GHz scored 255 MFLOPS: a 195.3% performance advantage for the G5 in this test. If we assume a direct correlation between MHz and MFLOPS for the P4 (which would actually overstate the performance of the P4) and increase the P4's score by 12.782% this would give the 3GHz P4 a score of 287.594 MFLOPS. This is still a 173.16% performance advantage for the G5, and NASA states that a 20% increase in performance for the G5 would be reasonable "when G5-aware compiler tools become available."

    So it would seem NASA's benchmarks go a long way in validating the benchmarks for the G5 that Apple released last month at the WWDC. In fact, NASA appears to be giving the G5 even better scores than Apple and Veritest did.

    The vector tests that NASA performed to test the G5's AltiVec instruction set produce some even more impressive results, and would be a good indication for why the G5 outpaced the Xeon and P4 by such dramatic amounts on real world tests (at times more than 700% faster than a 3GHz P4). "The vector version of Jet3D runs an order of magnitude faster than the scalar version (speedups of 10X-13X are typical)." The dual 2GHz G5 was benchmarked at 5177 MFLOPS (a 1040% increase over the scalar test) and 1.29 MFLOPS/MHz. This also seems accurate considering Ars Technica's claim that the AltiVec engine wasn't as well integrated into the G5 as it was in the G4. The 2GHz G5 (single cpu) scored 2755 MFLOPS, or 1.378 MFLOPS/MHz, which shows a slightly larger performance hit for vector operations than floating point operations when moving to a dual G5.

    Dak

    1. Re:NASA Verifies Apple Benchmarks? by baseinfinity · · Score: 5, Insightful

      Either way they're still benchmarking Apple hardware to be released in September versus Intel hardware that was available months ago. A quick look at Tejas and Athlon 64 specs will prove that both Intel and AMD have some whoopass coming down the line in Q4. At least this means Apple will be competitive still when the storm hits... but I don't think this hardware is revolutionary when compared to it's future peers.

    2. Re:NASA Verifies Apple Benchmarks? by andreMA · · Score: 5, Informative
      The 498 figure was presented strictly as an aside:
      Though dual processor benchmarks are not presented in detail here, it is worth noting that the G5 system benchmarked at 498 MFLOPS...

      More relevant, perhaps, are the figures in the raw MFLOPS graph:

      254: PowerMac G5, 2x2GHz, (single CPU only)
      255: Pentium 4, 1x2.66 GHz
      Alas, difficulties in cross-platform benchmarking rear their ugly head:
      Scalar Code:

      G4 using Absoft F90 v8: f90 -s -O -lU77 -N11

      P4 using Portland Group F90 v4.0-3: pgf90 -byteswapio -tp p7 -O1
      The author did apparently make an effort to use the compiler and flags best suited for each architecture if I read this correctly....

      Note that the higher level of optimization (-O2) and SSE/SSE2 options in the Portland compiler degraded Jet3D performance on the P4 system, and were therefore not used.

      I don't know how much I trust NASA tho. Afterall, they only do RealMedia and WindowsMedia streaming media. Perhaps there's some bias there in favor of Windows (yes, I realize that the testbed P4 system ran Red Hat. Lighten up)

    3. Re:NASA Verifies Apple Benchmarks? by nsrbrake · · Score: 5, Informative

      Go back and read the article. You have no idea what you are saying.

      1) One of the Mac's processors was disabled
      2) 195.3% advantage was on an MFLOP/MHz basis

      That is how they are comparing the architechture of the chip and it's performance outside of a MHz pissing race. They are in the same ballpark now MHz wise so why shouldn't they take a look at how the actual chip performs. Not to mention how much more will likely come out of the chip with maturing compilers to take advantage of the arch.

      --

      Bah!
  3. Only benchmarks that matter are.... by FooGoo · · Score: 5, Insightful

    The only benchmarks that matter is my impression of the system while using the apps I use. Everything else is opinion.

    --
    People who bite the hand that feeds them usually lick the boot that kicks them
  4. Re:The G5 by Dak+RIT · · Score: 5, Insightful
    Microsoft Windows XP Pro: Full price: $299
    Microsoft Windows XP Pro Upgrapde: $199
    http://shop.microsoft.com/Referral/Productinfo.asp ?siteID=10798

    MacOS X 10.3/2/1 Full price: $129
    http://www.apple.com/macosx/

    Microsoft Windows XP Pro (5 Users): $1315.60
    MacOS X 10.3/2/1 (5 Users): $199

    If you bought Windows XP ($299), and then can upgrapde to Longhorn for $199, you paid $498. If you bought MacOS X 10.1, 10.2, 10.3, and 10.4, you paid $516. Pretty similar, and that's assuming you only have to pay $199 for Longhorn. In the meantime, Apple users enjoy continued advance, while Windows stagnates for 4+ years.

    Do the same with a family licence of 5. Buy Windows XP for $1315.60, then upgrade for $875.60: $2191.20 (over 4 years, for 5 people: $109.56/user/year).

    Buy MacOS 10.1, 10.2, 10.3, 10.4 (5 User Licence): $796 (over 4 years, for 5 people: $39.80/user/year).

    Using http://shopper.cnet.com I found a copy of Windows XP Pro for $207, and an upgrade for Windows XP Pro for $177. I found a copy of MacOS X 10.2 for $98.

    If these prices hold over to the newer Operating Systems these companies release, then Windows would cost $384 (23% savings), and MacOS X would cost $196 (24% savings). If you bought every point upgrade Apple released it would cost $392.

    Dak

  5. Interesting Thought by ciroknight · · Score: 5, Interesting

    Apple has been making better software for years, everyone agrees; They just never had the hardware to back them up. Then every time they do crop up with better hardware, everyone criticizes them and says that it's just not possible, PC hardware is always better they say. But now they've proven you wrong... TWICE, and some trolls STILL don't believe them. It's a sad world. I just wish Apple would open up at least their motherboards a little more, make Macs more customizable, more like PC's so they can start dominating again.

    There's also one benchmark I'de love to see. Power Mac G5 vs Sun UltraSPARC III. It's fair: they're both 64-bit procs, and it would really make people look at it in businesses that only look at supercomputers as viable. Then maybe people would start giving Apple and IBM some credit.

    My 2 cents (Canadian). Thanks.

    --
    "Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
  6. Re:Turn the optimizations on first. by Phroggy · · Score: 5, Informative

    I hope they didn't use gcc (the yet-another free and hopeless compiler).

    It should be noted that Apple uses gcc to compile Mac OS X and most of their applications, so it would be appropriate to use gcc on the G5. Intel's compiler might be a more appropriate choice for the Xeon.

    --
    $x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
    $x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
  7. MFLOPS per $ by mgkimsal2 · · Score: 5, Interesting

    Why not show an mflops/$ chart? Related to my 'cost' post as well, but I felt it deserved its own post. :)

    This seems to confirm my belief that most mac people don't buy their own hardware, but get it through work or school.

  8. Vector Performance by Japer+Lamar+Crabb · · Score: 5, Insightful

    >>Vector performance of the G5 remains excellent, and is inline with current G4 systems on a per clock cycle >>basis. As a result, raw vector performance of the G5 will be boosted simply by its higher clock speeds relative >>to current G4 systems.

    This would seem to be one of the more interesting points made, actually. Prior to the announcement of the G5s, speculation on the PPC 970 suggested that it would be stellar with FP & so-so with integer; the real question surrounded how well IBM would implement SIMD. Many were pessimistic. Given that it seems like they've managed to add it efficiently a scaled-down POWER4 core, future refinements could make this series of chips (PPC 9X0s) real monsters.

    But the future viability of that roadmap (given how ruthless the company as a whole tends to be when faced with departmental money losses) depends as much upon the success of IBM's Linux strategy as it does on its success in the PowerMac line.

    [With apologies to BadAndy of the Ars Technica boards; thanks for sharing your insights.]

    --
    Habit is the ballast that chains the dog to his vomit - Samuel Beckett, "Proust"
  9. In all fairness... by Znonymous+Coward · · Score: 5, Insightful

    It's not Apple's G5, it's IBM's 970 and it's the shizzle.

    --

    Karma: The shiznight, mostly because I am the Drizzle.

  10. NASA never benchmarked the G5! by Anonymous Coward · · Score: 5, Funny

    It was a hardware simulator running on a soundstage.

  11. 5177 MFLOPS 288 MFLOPS by vitaboy · · Score: 5, Insightful
    This is the killer statement in the whole article:

    "The vector version of Jet3D runs an order of magnitude faster than the scalar version (speedups of 10X-13X are typical)." The dual 2GHz G5 was benchmarked at 5177 MFLOPS (a 1040% increase over the scalar test) and 1.29 MFLOPS/MHz."

    5177 MFLOPS when running a Velocity Engine optimized version of Jet3D.

    Now, how much does an P4 extrapolated to 3.2 GHz get? Like 288 MFLOPS?

    Someone please explain to me how 5177 MFLOPS and ~300 MFLOPS are even comparable.

    As the Mathematica guy said, the competition is no longer high-end PCs, it's now $10,000 UNIX workstations...and the G5 is still faster than any of them.

    No wonder the G5s smoke the dual Xeon in the Photoshop, Mathematica, Logic, and Luxology app bake-off. All these apps would have been optimized to use the Velocity Engine.

    If I were a scientist doing lots of image processing and vector calculations, I'd need a cluster of about 18 or so 3.2 GHz P4 machines to keep up with the dual 2 GHz G5 PowerMac running a typical Velocity Engine optimized app.

    That's a sweet 5177 MFLOPS for you - evidence the G5s rock as hard as Apple has been indicating.

  12. Re:Damn Dude, RTFA by dhogaza · · Score: 5, Insightful

    Except that

    1. They weren't using a compiler optimized for the G5, and expect performance to increase when they have that opportunity.

    2. Dual G5s appear to scale better than dual P4s. They're getting close to 2x performance with the dual G5s, much better than most folks are used to with SMP systems.

  13. Re:If I remember right... by Filarion · · Score: 5, Informative

    actually you only need 3 db to double the volume (which, btw, has little to do with loudness). and 1000 dBa is, I hope, impossible.

    --
    --[Nothing important]--
  14. Re:And before anyone asks... by mamer-retrogamer · · Score: 5, Informative
    The G5s are Apple's flagship product line. Comparing el-cheapo Dell's to high-end Apple's is like comparing... well you know where I'm going with this train of thought (something about oranges, I think).
    How about a more fair comparison? Namely, between similarly configured high-end single-processor systems:

    Apple PowerMac G5:
    1.8GHz PowerPC G5
    250GB Serial ATA - 7200rpm
    SuperDrive (DVD-R/CD-RW)
    512MB DDR400 SDRAM (PC3200)
    Mac OS X
    AppleWorks
    ATI Radeon 9800 Pro
    56k V.92 internal modem
    No Monitor
    $2874

    Dell Dimension XPS:
    3.2GHz Pentium 4
    200GB Ultra ATA - 7200rpm
    DVD+RW/DVD+R/CD-RW
    512MB DDR400 SDRAM
    Microsoft® Windows® XP Professional w/ Microsoft® Plus!
    Microsoft® Works Suite 2003
    ATI Radeon 9800 pro
    No Monitor
    $3062

    And if you are to believe the benchmarks, it seems that Apple is selling the faster system for a lesser price than a similarly configured Dell.
    Apple has never competed at the low end. It is not starting now.

    -Mike

    --
    Schrödinger's cat is not amused—maybe.
  15. Re:Turn the optimizations on first. by dhovis · · Score: 5, Interesting

    I think the thing that most people on /. seem to keep missing is this: MacOS X and Linux both use GCC as their primary compiler. The Linux kernel is compiled with GCC, as is Darwin. Most software for each platform is compiled with GCC.

    Now, with all these Linux-heads around here insisting that Linux is faster than Windows on x86, you'd think GCC for x86 might be a good compiler. Certainly the SPEC tests Apple (and Veritest) did with GCC on the G5 with OS X and the dual Xeon Dell with Red Hat had to have been a valid comparison between those two situations.

    I also keep seeing all these comparisons to Dell computers without full specs of the Dell. The base configurations for the PowerMac G5 is positively loaded. How many $500 Dells come with Gigabit Ethernet? How many have the same level of engineering into the thermal managment?

    Only time will tell for sure. In the mean time, remember that IBM will be producing blade systems with the 970. We'll get a chance to compare those as well eventually.

    --

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

  16. Re:5177 MFLOPS 288 MFLOPS by Anonymous Coward · · Score: 5, Informative

    I recently got the chance to do a testrun, doing some airflow simulation on a G5 1.8GHz demo machine, and with altivec optimizations it clocked in at roughly 2100MFLOPS average for 5 runs(I could probably get better results with a better compiler though), while the dual Opteron 1.8(which the place where I did the testrun has bought 10 boxes of for their renderfarm), running Suse Linux, and my program re-compiled for x86-64 and SSE2 performed at about 2960MFLOPS average, but that could probably be improved with a better compiler too, but I had to use GCC at this time. Both machines had 4GB RAM btw.

  17. Re:fortran compiler by wagnerer · · Score: 5, Insightful

    You'll want to be careful with the code the intel compiler spits out. It may be fast but some scientific codes compiled with it give incorrect answers. Compile the same code on any other f90 compiler and it gives the correct answer. Not something to inspire confience in your answers.

  18. Re:SETI by I+Like+Swords!!! · · Score: 5, Funny

    Yes, but just think of how much MORE static you can have SETI run computations on... It's like watching a blank tape in fast-play.

    --
    .unsigged