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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."
"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."
First, 498 vs 255 is 95.3% (instead of 195.3%) advantage.
Second, why compare dual fastest G5 vs single mid-range P4? Singe 2GHz G5 scored 254 MFLOPS, it quite fast, but then again equally fast 2.66GHz P4 is available at $188.
It would be much more interesting to compare dual 2GHz G5 against dual Opterons and Xeons.
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
Microsoft Windows XP Pro Upgrapde: $199
http://shop.microsoft.com/Referral/Productinfo.as
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
It was interesting to see this paper devote so much effort to the completely useless metric of MFLOPS/MHz. This measurement has absolutely nothing to do with performance, but rather, with the approach taken by the chip manufacturer. You can do more in one clock cycle, as AMD historitcally has done, or less, but optimize for faster clock speeds, as Intel has in recent flavors of the Pentium.
One might be tempted to design a chip that does more in one cycle and then clock it as fast as a chip that does less in one cycle. Unfortunately, while reality is a little more complex than this, the basic reason is that the more a chip does per cycle, the more heat it generates per cycle. If you try to squeeze too many cycles through it in a second it will fry.
So showing that the G5 has better performance per clock cycles is no more useful than showing that an AMD chip has better performance per clock cycle than an Intel chip. All that matters is how much performance you can get from a chip before it cannot be clocked any faster without requiring unreasonable cooling methods.
All this paper shows is that, while the G5 is designed to do more in a clock cycle than a P4 is, the chip tested is ultimately not any faster than the P4 they benchmarked it against. It remains to be seen how the G5 will do at higher clock speeds. With this in mind, it would be *far* more useful to see heat dissipation stats on the G5 since that might give us some idea how close to it's design limits. If it is cranking out high-end P4 performance and running cool *then* I will be impressed.
Maybe because that was the hardware and software available to the testers. Contrary to popular belief, government employees do not have unlimited budgets to buy stuff. The last time I worked in a government office, some of the furniture was older than I was and my PC was built from scrounged parts.
Mea navis aericumbens anguillis abundat
Mac is cheaper than PCs, even in laptops. It all depends on what you'll use it for. I'm trying to convince a pal that the iBook would be a better purchase for his mother than a Fujitsu Siemens PC. The iBook is rougly 9500 NOK and the Siemens 11500 NOK.
The difference in speed mHz, RAM etc. is irrelevant for a person just getting used to computers and the net. When she is having weekly problems with the Siemens / Windows machine, it will be lost money in time. While the Mac is cheaper in usage, because of less "frustration time" and less hassle.
This is an argument I would strongly disagree with, if you asked me two years ago. But since then, I have come to the conclusion that the Mac simply work better for the lay people. It does the work, and faster because there are less frustrations and less hassle.
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.
>>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"
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.
"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.
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.
Well, that is exactly the sort of claim that needs to be verified by testing.
Given that the 2 processors are (presumably) sharing 1 video card, one set of RAM chips, one I/O system, and one disk drive, surely there must be *some* kind of performance hit from sharing the rest of the machine with a second processor? Or some performance drain from putting all the housekeeping talks onto just one of the 2 processors?
I think this adds weight to my original point - that benchmarking a dual G5 against dual amd or intel systems is the only way we'll settle this 'fastest PC' question, and that arbitrarily shutting half the sysem off isn;t a sensible way to test things.
A pizza of radius z and thickness a has a volume of pi z z a
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.
By a whopping 0.4%, and with one of the G5's processors disabled. You can spin it any way you want, but the clear fact is that with the G5 Macs are competitive in CPU performance again. I don't see why this disturbs you so; competition is good.
How to solve most of our problems: 1.Lots of nuclear plants. 2.Cure aging.
My take.
Since everything inside the G5 is "point to point" then unless both CPUs need to talk to exactly the same thing at exactly the same time then the performance hit will be almost impossible to detect. (I wonder how RAIDing drives could make this overhead even more improbable?)
Since there is a lot of Mach-ness in the OS X kernel I would also think that there aren't too many critical regions there that force the use of only one CPU. In other words, I think the situation is better than that kernel (was it an early Solaris?) that had one mutex around the whole kernel.
As usual, anyone willing to pay me to benchmark one of these puppies for them? :-) The machine is suitable payment.
------- MacOS X, WebObjects, Apple (G5) hardware triply tied
You wanted to say year ago? Month ago Intel released 3 GHz, 800 MGh FSB P4 and new chipset for dual DDR 400 motherboards. Comparing G5 against older 533 MGh FSB processors on old chipset is hypocrisy.
Even 2.6 GHz 800 MGh FSU processor with i875 chipset-based motherboard and dual DDR 400 memory behaves much better than that 2.66 GHz processor.
MSDOS: 20+ years without remote hole in the default install