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Comment by CharlesW | Hacker News Reader

> In this instance, Apple would likely be going to a less powerful processors…

Arguably, the A11 Bionic is already faster than mainstream desktop CPUs.

"The iPhone 8 even edged out the score from the 13-inch Apple MacBook Pro with a 7th-generation Core i5 processor. That notebook notched 9,213. Is Geekbench 4 really comparable from phone to desktop? According to the founder of Geekbench, John Poole, 'the short is answer is yes that the scores are comparable across platforms, so if an iPhone 8 scores higher than an i5, then the iPhone 8 is faster than the i5.'"[1]

[1] https://www.tomsguide.com/us/iphone-8-benchmarks-fastest-pho...

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A 6-core CPU beat a 2-core one in a perfectly scaling multithreaded benchmark? That's just shocking! Truly, that is definitely, unquestionably, beyond any doubt representative of what a battle at the workstation level would be.

But more seriously and less snarky there's a reason they used the 13" macbook pro there specifically and that's because the 15" with the quad-core i7 destroys the A11, 15k vs. 10k. Of course that's with wildly different power & thermal budgets, and I haven't seen much reason to think these geekbench results are at all representative of anything, so grains of salt and all that.

Don’t forget that the current gen A processors are designed to run in something with a tiny battery compared to a laptop. It’s likely that any MacBook bound Apple CPU won’t have such a limitation and will be able to run much faster as a result.

Also if you look at the performance trajectory of A-series in the last five years, 2020 sounds about right for where the crossover will come even between iOS based A-series processors and the fastest of what Intel has to offer, provided they can keep up the pace of performance improvement.

Why would Intel stand still while arm improves dramatically?

Apple has been gaining on Intel while both have been improving. He’s projecting where those lines cross.

> Apple has been gaining on Intel while both have been improving.

Have they really, though? What lines are actually crossing? Intel's mobile CPUs have continued to shed power, so how much of this is actually Apple "catching up" to Intel vs. Intel just optimizing for power at the cost of performance? As in, is there any performance gap that's actually shrinking, or are phone SoCs just getting more power hungry while laptop ones are getting less power hungry?

Because phone SoCs have gotten rather monsterously power hungry compared to years past. They are actually 5w under real world load parts now, with devices just letting them thermal throttle rapidly to achieve higher burst rates. Laptops, by contrast, are ~10w TDP, vastly less than they were a decade ago.

This would probably make a fascinating in-depth analysis, but the singular data point of a 5w SoC being within spitting distance of a 10w SoC is hardly a revolutionary story. It's pretty much what you expect.

but the question would be:

will apple up the battery requirements for their own cpu/gpu, or would they simply drop battery while striving for a thinner laptop?

this from someone who's been buying/using Macs for a long time - I'd love to see some very fast arm competition, but is that what it'd really turn out to be?

> It’s likely that any MacBook bound Apple CPU won’t have such a limitation and will be able to run much faster as a result.

Geekbench is based on the unthrottled peak performance of the CPU. Increasing the TDP headroom eliminates throttling but Geekbench doesn't measure throttling.

You can perhaps increase performance by overclocking but this requires the CPU to be designed for higher frequencies. AMD's Ryzen CPUs usually top out at around 4 GHz. Intel's CPU can be overclocked up to 5 GHz. The maximum clock speed is limited by the slowest component of the CPU. If the slowest operation takes 0.25 nanoseconds to complete this limits your frequency to 4GHz. If Apple had enough foresight to design their chips with this in mind then maybe but in reality they probably optimized the chip entirely for mobile TDPs.

Faster != Faster. Adobe and Autodesk likely have many architecture specific optimizations, and take advantage of the large x86-64 instruction set.

Geekbench is a poor tool. Maybe for simple mathematical operations, but x86-64 has a larger instruction set than what the A11 supports

I dont think there is strong connection between a larger instruction set, and performance.

You are 100% correct.

Using a bad example, let's say x86-64 and A11 can both add numbers up to 3 digits. The a11 can do that faster than x86-64. But I want to add a 5 digit number. The x86-64 can do that with one instruction, but the A11 has to break that 5 digit number into multiple 3 digit numbers in order to process it.

From my understanding, which might be wrong, Geekbench only tests what both can do. Comparing a pickup truck and a sports car you need to look at more than just how fast they can do. You can both move furniture, but the sports car will need to do a lot more to be able to what the pickup can.

This doesn't make any sense.

Yes, Geekbench is a terrible CPU benchmark, but both of them are Turing complete, so there is no functionality difference. And complex instructions are broken into uOps in x86 too.

On the other hand, Apple hasn't been shy about putting fixed function hardware on the Ax chips to eke out the maximum performance for a given power budget. They were much faster at adding h265 decode/encode than Intel, for instance. I would imagine they'd spend their (larger) transistor budget on a lot of this type of dark silicon that would assist in speeding up common operations.

Geekbench doesn't benchmark single instructions.

Faster is not necessarily more powerful.

...in one benchmark, from a heavily Apple-favoring company.

I'm sorry, we need better evidence.

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