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Comment by mbertschler | Hacker News Reader

This is so wrong. They are acting if processors can only get better by increasing chip speeds. If that were the case todays quad core CPUs with 3GHz should match the performance of a Pentium 4 3GHz * cores, which is definitely not the case.

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You're making an extremely uncharitable reading, especially give the author. The article specifically acknowledges that there are other ways of increasing performance, which is exactly what CPU manufacturers have been concentrating on for the last decade. And where they're getting that extra performance from (e.g more cores or extra IPC through larger cache, better branch prediction, extending the ISA, etc) you're going to need more transistors.

The real point of the article is what happens to the hardware ecosystem once the density scaling stops. Not the exact mechanism by which node advances have been translating to improved performance.

Probably I don't really get the point of this article, or the exact changes in the hardware ecosystem when the density scaling stops? Because although scaling became harder recently, I don't think we have reached the point where the processing performance increase per year is slowing down.

I have a problem with that paragraph: Even if it takes a couple of years and several iterations for a self-taught engineer to reproduce, the resulting product isn't terribly out of date: the iPhone has only undergone a modest increase in clock rate over the past four years, from 1GHz in the iPhone 4 to 1.4GHz in today's iPhone 6. This relative stagnation is endemic, leaving a large window of opportunity for engineers to learn from and emulate the designs of the best.

The iPhone 6 was released with iOS 8, which doesn't support the iPhone 4 anymore. Also the CPU performance of the A8 in the iPhone 6 has 12x the performance of the iPhone 4. If you still want to use current apps, an iPhone 4 is really outdated.

On the other hand for the Novena laptop of the author the same principles might not hold true, but that has more to do with software than hardware, because especially Linux works very well with not so recent hardware. In my experience Android and iOS software became way more processing power hungry than desktop software did over the last 4 years.

Depending on what you mean by processing performance, the increases did slow down, significantly, around 2004-2005. At least for non-numerical single-threaded workloads. Had they continued at the same rate, CPU performance would be anywhere between 5 to 10X higher today.

This is a commonly used motivation for a lot of modern computer architecture research, here's one such plot: http://liberty.princeton.edu/Projects/AutoPar/

GPUs are a better measure of performance improvement, because they more easily add cores, and so aren't as affected by the clock rate plateau - for GPUable computation.

I'm pretty sure that a single core of a modern CPU is much faster than Pentium 4 at the same clock rate. As a result, I believe that a proper parallelized code running on a modern quad core CPU would be much faster than the same code running on 4 P4s.

This is what I meant. While I looked over some benchmarks I saw that a single Haswell thread for example seems to be 3-4 times faster than a Pentium 4.

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