Yet another Hacker News

Retrospectively Reverse-Engineering Apple's Neural Engine

65 points zdw 1 hour ago 9 comments

LoganDark 1 hour ago | parent

> what workloads it was designed for and accels at.

excels!

osquar 1 hour ago | parent

At least we know it wasn't written by a bot

pbhjpbhj 52 minutes ago | parent

Could've been a pun as a neural processor is an accelerator, so it 'accels' at machine learning tasks!

CraigJPerry 50 minutes ago | parent

This isn't ai slop. It's fascinating and well written.

But I learned something really basic - i didn't know that the ANE (and the data pipeline around it) was designed for CNN rather than transformers. It's always been an open loop in my head, wondering why the ANE was less impactful than i understood it should be.

msdz 39 minutes ago | parent

> But I learned something really basic

Same for me!

Also, just imagine being the group at Apple responsible for designing this section of the chip, starting probably almost a decade back – under the constant uncertainty of not knowing what direction ML workloads would develop in…

eastbound 17 minutes ago | parent

I'm all for compassion, but engineers knew the NE was empty when it sat idle for 10 years on our computers.

- when you're given no usecase for your engineering piece, apart from "detour characters in pictures". It's an exageration but AI's contributions in iOS aren't visible; Meanwhile Google has features that people actually notice like removing tourists from your holidays photos — worse: it's mostly a simple collage feature working on the main CPU, and it has the same social effect as green bubbles in iMessage ("ah. Tourists on your photos. iPhone user?")

- and you tout it as "16 Neural Engine cores" during the sales, with no associated software, no listed material feature, just hand-waving,

- Siri maxxes out at "There is no contact named 'What's the weather today' in your agenda",

Then can't really claim that Apple engineers' problem was really the bad luck that ML wasn't the determining part of the future. It's more like misreading the room for 5 to 10 years straight.

Apple engineering's excellence on vertical integration and supply chain control gave them absolute power over our world (with merit), it just failed at that particular project. Which occupies 40% of our CPUs.

troupo 5 minutes ago | parent

ML research was a rather known quantity, or the separate "Neural Engine" CPU explicitly aimed at existing ML pipelines wouldn't exist.

However, very few used it for anything, even within Apple. I feel like it was a huge wasted opportunity.

riedel 37 minutes ago | parent

A lot of neural engine, particularly in the embedded domain (ARM/RISC MCUs) have the same problem. Designing other models means on top of this means a lot of profiling to get convolution blocks right to get good speedups. (We optimized this in the past e.g. using Neural Architecture Search on super networks)

zozbot234 28 minutes ago | parent

How does this relate to the more recent work on the M4 ANE found at https://maderix.github.io/articles/ ? Does the M4 and later ANE expose any additional capabilities, or is it just a higher-performance iteration of the same thing?

As an aside, the introduction to this article seems to conflate the ANE with the Neural Accelerators (NAX) found in the M5+ (and A-series equivalents) GPUs. These are very different things, and Apple is still working on the ANE - the M6 and A20 will apparently feature doubled ANE blocks.