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Apple's G5 Speeds Challenged
An anonymous reader was the first of a seemingly infinite stream of people to submit a URL to an argument that makes the case that the G5 isn't quite what Apple wants you to think of it. The evidence? Apple's own press material. Worth a read.
I watched the video. (http://stream.apple.akadns.net/ - requires QuickTime). Now, I'm sure there's many ways you could tweak the benchmarks and so forth but the Photoshop and Mathematica benchmarks rocked. The G5 was 2x faster than the Xeon.
I used to get involved doing benchmarking back in the good old days of Whetstone when I worked on supercomputers. Every manufacturer had a different nasty tweak to the compilers that were pulled out only when it was time to do benchmarks for a customer. The mantra then as now was: the best benchmark is the app you want to run (since most buyers of supercomputers write their own apps, porting them for a benchmark was a possibility).
The G5's may not be the hottest thing on the planet but they're close enough to get Apple back in the ball game. Nice systems architecture, nice case and the claim is they're quiet as well. Oh, and don't forget you can put in 8GB of RAM. Now even OS X doesn't need to swap :-)
The 1GHz backplane is the real news. No processor benchmark test really takes into account the total real speed of the system when running applications.
The fast backplane will speed up IO, which is a common bottleneck. 1GHz for a PC backplane is huge. The only machine I had seen a 1GHz backplane in so far is a HP-UX server. It cost wayyy more than $2000 or even $3000.
I really believe that with this new chip alliance with IBM Apple will finally be able to put that "the OS is really cool, but PCs are always faster" stuff behind them.
Yesterday was a good day for apple.
And ironically, the problem is that they didn't benchmark differently enough: Apple used GCC to compile SPEC on the P4 and Xeon, as well as on the G5.
While this eliminates one variable from the comparison, it also eliminates a hefty percentage from the SPEC numbers one can get with Intel's compiler.
gcc produces inferior code on both platforms. Intel's C compiler kicks the shit out of gcc, and likewise metrowerks C and IBM's C compiler kick the shit out of gcc too.
gcc's x86 backend has had a lot more work than the ppc backend.
It would be interesting to see intel's C on x86 vs IBM's C on PPC. Compare chips and compiler writers with one stone :)
If they would have just taken Gcc "out of the box" and benchmarked what you said would have been true. But they heavily optimised gcc by adding G5-specific code (from IBM's compiler? I hope IBM hasn't stolen it from someone else ;) and specific "lax" malloc() routines etc...
The guy may, or may not be a troll. However, the sheer amount hate mail, and the level of it, was stunning. What kind of people write stuff like that? Very few of them even attempted to address the guys points, and those that did made a hash job of it (nobody uses int math? wtf?)
Did you notice how almost all of the hatemail was addressing him in the third person?
He went onto a discussion board somewhere about the post (probably MacNN, probably one of the worst reputation Mac websites in terms of brainpower) and just cherry picked the comments he could take apart easily.
It's not like he actually *got* that hatemail. He didn't even post an email address with the article.
Isn't it funny how you can bend things to make you look favorable - just like Apple may have done?