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These comparisons (from the quote) often come up with ARM vs x86, but they're always comparing apples and oranges. Yes, you can fit an ARM core with 1/4 the performance in, say, 1/16 the power envelope, but you can do that with x86 cores as well. The cores we've got are still heavily optimized for single thread performance, because that's what the market demands. Even embarrassingly parallel domains like web serving have increased latency, and Amdahl's law is a problem for most real world programs. The penalty paid for this is high, due to diminishing returns due to caches, complex architectures, and (roughly quadratic) power increases due to higher clock speed. Ignoring the obvious ARM versus Atom low end comparison, Intel is readying Knight's Landing, their 2015 Xeon Phi product. It's going to include 72 Atom cores, with 288 threads, and be able to be socketed in standard Xeon motherboards. That's 1152 Atom threads on one commodity(ish) server (and the first time I've ever used a calculator to determine the thread count of a server), and it looks a hell of a lot like the picture being painted by many ARM vendors. Many lightweight cores, great power efficiency and peak performance, and most likely not necessarily suited to latency sensitive tasks. I don't think it's about ARM versus x86 at all, it's more about a new strategy for computation. Intel can't transition its traditional x86 processors over to the new model, so they're starting to make Atom a first class Xeon product (both with low power standard Atom chips already released, and the Xeon Phi). The market will shift the other way too - we're going to see ARM processors from multiple vendors that rival at least AMD's x86 offerings in terms of performance per core. And power consumption, too. After that, there'll be products on both ends of the spectrum from both architectures, and then maybe we can start to move past the false dichotomy of ARM having efficiency and x86 having performance. |