Comment by OldSchool | Hacker News Reader

Comment by OldSchool | Hacker News Reader

After reading about great performance of newer ARM-based offerings I was surprised when I compared real-world performance at the same clock speed recently: ARM doesn't even come close to any recent-generation x86. This is certainly one very important measure of architecture.

A quick sunspider test with a US Samsung Galaxy S3 1.5GHZ snapdragon on Jelly Bean's likely highly-optimized browser shows performance very comparable to a first generation intel 1.66GHZ Atom 230 single core on the latest Firefox. Granted it's a mostly single-threaded test anyway but the ARM has both cores available and the test is pretty cpu-bound after it starts.

I'd estimate the latest i7 is at least 3x faster per-GHZ on this lightweight but fairly general (cpu-wise) test.

For heavy lifting, a recent i7 with it's cache size, memory bandwidth and accompanying i/o would probably compare to an ARM that is running at about 5x the clock speed.

I don't think that ARM can be suddenly declared the best at anything other than maybe performance-per-TDP.

Performance-per-cycle is the more difficult problem to solve... ask AMD how hard that's been since the original Intel core series appeared on the scene in 2006. Prior to this and after it wasn't just a chip clone maker, AMD dominated this metric.

But performance per TDP is what matters. Battery technology is getting better much slower than CPU technology. We're already at the point where CPU speed is "good enough," but we're not at the point where battery life is "good enough."

I've downsized from a Core 2 MBP to an iPad. It has 1/4 the RAM and runs at half the clock speed. Do I care? No! Web browsing is fast and fluid, photos load plenty fast, editing documents in pages is plenty fast. And it lasts through my whole 12+ hour workday, letting me leave the charger at home and often not even bothering to charge it every night. That's huge and much more important to me, and I'd imagine most people, than whether it can be imperceptibly faster.

I agree for typical single-user applications, but it's hard to call that the end of x86 as in the article. If ARM were matching x86 cycle-by-cycle in performance for less power that might be a credible claim that servers were next. Also high-end x86 devices run higher clock speeds with more cores so the gap in absolute performance is at least 1000% percent wide. I just don't see ARM displacing Intel when batteries or at least small form factor aren't involved. I don't expect to have an x86-based phone or tablet either.

My opinion (and I suspect the authors) is that the market for chips where batteries or form factor are not a concern will no longer be large enough to support a company of the size of Intel. RIM makes the finest high security physical keyboard phones anywhere. That is now a market sized for a company 1/10th their current size.

Exactly - The latest A15 benchmarks show the ARM chips being competitive speed-wise (in terms of computation power) to the first Core-2 Duo from 2006. Intel are 6 years ahead.

Yeah, the ARM cores have the power advantage generally at the moment, but under load there won't be much difference looking at what Haswell's ULV seems to be promising compared to the A15, and you can bet that the Intel chips will leak at idle much less and will probably have better sleep states.

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