At WWDC 2020, Apple announced that its entire Mac product line will be transitioned to a new processor architecture within the next two years - those processors being designed by Apple itself. Here's everything you need to know.
What is Apple Silicon?
Apple is calling its architecture Apple Silicon, but it will be the same, self-developed Ax chips, that have featured in the iPhone and iPad for years. At their core, these processors are based on the ARM architecture, but they have long been adapted by the Apple chip design team to suit the requirements of the iPhone and iPad, and provided with their own features (e.g. machine learning capabilities).
This chip architecture will now be applied to the Mac. Optimisations and improvements to the ARM architecture should ensure that the performance of an ARM Mac does not lag behind that of current Intel Macs. To demonstrate this, Apple ran Final Cut Pro X and Adobe Lightroom on an Apple Silicone prototype. The Apple Silicon-equipped Mac executed the programs impressively smoothly. However, Apple did not reveal specific benchmarks.
The pros and cons of switching from Intel
The big advantage of this change is obvious: Apple will have the hardware of all of its platforms (iPhone, iPad, Apple Watch, Apple TV and Mac) completely in its own hands and will be able to tailor it to the respective requirements.
However, what happens to technologies like Thunderbolt 3 (which comes from Intel) is still unclear. It is unlikely that Apple will license Intel's Silicon Thunderbolt. We speculate that it will adopt USB 3 or introduce another proprietary interface technology.
Which apps will work on Apple Silicon?
The operating system itself, as well as all Apple programs, will be available natively on the new platform from day one. We mentioned already that Apple ran Final Cut Pro X and Adobe Lightroom on an Apple Silicone prototype.
Adobe is also already working on converting its Creative Cloud and Microsoft's Office will also run natively. This is good news because it shows that Apple is serious and the big software houses are getting involved right from the beginning.
Virtualization tools such as Parallels Desktop should also continue to be possible. Apple also showed a Debian Linux that ran as a virtual machine in Parallels Desktop. However, it was not clear whether the Linux system itself was compiled on ARM chips. Linux has long been available for different processor architectures. We didn’t see Windows 10 running on Apple Silicon.
Senior Vice President of Engineering and Customer Support at Parallels, Nick Dobrovolsky, said that: "Parallels is proud to be working closely with Apple during this exciting transition, and we’re looking forward to launching support for future Macs with Apple Silicon."
What will developers need to do?
The changeover will primarily be achieved by recompiling the existing source code for the new architecture. That means that developers will have to create new versions of their programs and upload them to the App Store. This should be a simple process: Apple said that most projects should be portable within a few days.
However, for best performance, developers may need to make adjustments to the way they use hardware resources. Apple recommends that developers should reduce dependency on hardware and, if possible, use higher-level technologies. Apple mentions Grand Central Dispatch as an example, which should be used with multithreaded apps instead of creating and managing the threads itself.
The central tool for porting is a new version of the Xcode development environment, which Apple always makes available free of charge for developers. When compiling, Xcode 12 now creates so-called Universal 2 Apps, which contain the code for both Intel and ARM processors.
Despite this, programs that the developers cannot port immediately should still work on the new hardware platform right from the start. This is made possible by the inclusion of a translation unit that works in a similar way as Rosetta did when switching from PowerPC to Intel chips. The new system is called Rosetta 2.
Apple’s Craig Federighi explained that the code was translated to the new architecture when the programs were installed. This suggests that it uses a type of cross compiler that is triggered via the Mac App Store. If you download a program from the App Store on a Mac that is already based on the new architecture, the machine code of the app is translated to ARM during the installation.
This will save a lot of time and computing power when the app is running. However, it suggests that Rosetta 2 might only be used for programs that are installed via the Mac App Store. Apps that are obtained from other sources either have to be translated at runtime or that Apple will offer a special tool for this. The details will likely come to light in the course of WWDC.
What won't work?
Intel kernel extensions will probably not work. It is also said that not all Intel commands can be translated into the ARM architecture. Developers report limitations on so-called AVX, AVX2, and AVX512 vector instructions that cannot be translated. Intel programs that use these instructions will either not work at all or will be significantly slower.
Will iPhone and iPad apps run on the new Macs
A side effect of the new architecture that should not be underestimated is that iOS and iPad OS programs will run natively on the new Macs. This gives Mac users millions of new applications in one fell swoop, making the Mac the largest gaming platform in the world. A brilliant move. How special hardware features, such as multi-touch gestures, gyroscope, acceleration sensors and compass (which are often used as control functions in iOS games in particular) are to be implemented on Macs without this hardware is still unknown.
Details of the Mac mini for developers
Apple has not yet released a Mac product based on Apple Silicon - the rumour of a new ARM-powered MacBook has not come true. However, Apple is offering a special Mac mini equipped with Apple Silicon to developers.
This Mac mini will have the following specs:
macOS Big Sur developer beta and Xcode
It will cost $500 as part of the Universal App Quick Start Program - but at some point Apple requires that the unit should be returned to Apple.
As for the consumer model of the Apple Silicon Mac, according to Tim Cook, the first Mac with Apple Silicon should come on the market at the end of the year. You can read what we know about the Apple Silicon/ARM Mac here.
The transition period will take two years, according to Cook, until then Macs with Intel CPU will continue to launch.
This article originally appeared on Macwelt. Translation by Karen Haslam