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Comment by dna_polymerase | Hacker News Reader

The ARM comparison in terms of power efficiency doesn't really make sense, does it? I guess he's right about the efficiency but there isn't a real competitive ARM-based laptop available right now, at least I haven't heard of one and even if there is one: Apple couldn't just go for ARM they'd have to adapt their OS for that and I assume by now there is a lot of code in there making use of x86 quirks not easily adaptable to ARM

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Apple couldn't just go for ARM they'd have to adapt their OS for that and I assume by now there is a lot of code in there making use of x86 quirks not easily adaptable to ARM

I don't think the OS is the problem. First, macOS went through PowerPC -> x86 -> x86_64. Secondly, iOS and macOS share a lot of components, including the kernel.

More difficult would be moving the app ecosystem. Apple could do PowerPC emulation with Rosetta, because Intel CPUs had leapfrogged PowerPC by quite a wide margin at that point. It's probably a more difficult feat to put off with x86_64 -> ARM. Though, I think Windows ARM (at least) does x86 emulation.

That said, Apple has a lot of leverage with/over the ecosystem. Most macOS/iOS developers are already used to having to fix their applications for the next macOS/iOS iteration, so Apple probably won't have much trouble convincing developers to add ARM as a target.

However, if this happens, we'll probably have fat binaries for some years again. For backwards compatibility, but it's also likely that they are not at the point where they could replace the Mac Pro yet.

It would be smart for them to do the transition though. They would not be dependent on Intel's cycles and product decisions anymore.

If you're not actively following Mac stuff you probably wouldn't know, but there's been aggressive rumors for the last few years that Apple's going to switch to ARM for its laptops/desktops.

Here's a recent rumor summary: https://daringfireball.net/linked/2020/02/24/mck-arm-mac-202...

With the key motivator being:

> The reason for Apple to move Macs to its own in-house ARM chips is much simpler than that. (1) Apple’s laptop chips are better than Intel’s — they’re faster and more power efficient. (2) Using their own chips puts Apple in control of its own timeline for product updates. Why did it take so long for Apple to get the retina MacBook Air out the door? The one-word answer I was told by a high-perched little birdie: Intel.

> Apple couldn't just go for ARM they'd have to adapt their OS for that and I assume by now there is a lot of code in there making use of x86 quirks not easily adaptable to ARM

If you think Apple doesn’t have macOS running on ARM today, then you’re probably missing something.

I guess it could make lots of sense for them to support ARM and build ARM-based devices, that said I'm not an Apple dev in any capacity so I don't know what's going on internally. But right now there is now ARM-based Apple device running MacOS, is there?

Ummm... iPhones? iOS and macOS share almost completely the same kernel (https://github.com/apple/darwin-xnu).

I doubt they'd have much trouble. Apple's ported from 68K to PowerPC then to x86. The original NextStep OS ran on 68K, x86, Sparc, and HP PA-RISC. And I'd argue that the "hard parts" of the ARM port were already done with iOS.

iOS, tvOS, and watchOS share a great deal with macOS (past the surface, they’re almost identical). They’ve probably had an ARM build of macOS running internally for years now, much as they had an x86 version of macOS years before the PowerPC -> Intel transition.

The transition will be harder for third party devs, but there having been popular ARM Apple platforms for over a decade will speed things up considerably. Many Mac apps will have ARM versions available overnight.

Lots of Chromebooks are ARM, and many can run standalone Linux. Trouble is Linux-on-ARM is always more of a hassle than on Intel. Hence it's a chicken/egg problem: For Linux to support ARM better, there needs to be a great ARM laptop. And vice-versa.

There is a solid Windows ARM64 laptop, sort of: Microsoft's Surface Pro X. The main problem, as far as I can tell, is that there are few native ARM apps for Windows (though the MS Edge browser is native ARM64), and the machine is limited to running x86-32 (no 64 bit) apps through a translation layer, which makes the apps seem slow and makes the machine power hungry. But I would definitely consider getting one if I planned on living in the WSL, which is a native ARM-based Linux:

See, e.g.,:

https://www.theverge.com/2020/1/28/21100071/microsoft-surfac...

https://andregarzia.com/2019/12/a-week-with-the-surface-pro-...

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