You have to imagine that yesterday was a pretty good one for the folks at Arm—the little understood, but highly influential chip design company. Not only were they able to report that their designs power the world’s fastest supercomputer, there’s also that little detail about Apple choosing to switch from Intel-based CPUs to Apple designed custom silicon built on Arm’s core architecture for future generations of Macs.
A word on the supercomputer news first. Every year at the opening of the ISC high-performance computing conference, the organization running it releases the Top 500 performing supercomputers. As with most years, this year’s list was utterly dominated by Intel-based machines, but there was a surprise at the top. For the first time ever, Arm-based chips (in this instance, built by Fujitsu) are the CPU brains being used in the number 1 ranked machine—the Fugaku supercomputer, which is operated by the RIKEN Center for Computational Science in Japan. In addition to the prestige, it’s a huge psychological win for Arm, which has been working to make an impact on the enterprise computing world with its Neoverse CPU architecture for the last several years.
In the personal computing world, Arm notched an equally impressive victory with the official unveiling of the long-rumored Arm-powered chips for next generation Macs. Apple doesn’t have the largest market share in the PC market—it’s around 7% or so overall—but its impact, of course, greatly outstrips those numbers. As a result, by making the official announcement of custom Apple Silicon for the Mac, which was designed leveraging Apple’s architectural license of Arm’s chip IP designs (though Arm is never mentioned in the keynote or any of the press releases for the event), Arm scored a huge gain in credibility and awareness.
Of course, awareness doesn’t translate to success, and as exciting as the development may be, there are a great deal of questions, as well as previous history, to suggest that challenges await. First, while Apple talked about switching to this new design to both improve performance and reduce power consumption, it has yet to show any comparative benchmarks to existing Intel-based Macs for either of those metrics. Of course, that’s likely because the silicon isn’t done. Heck, Apple didn’t even announce the name of the new chips. (The A12Z Bionic chip in the developer system, and currently in the iPad Pro, is likely only an interim solution.) My guess is that we won’t get any of these details until the end of the year, when the first-generation Macs with these new chips are unveiled.
Apple’s primary stated reason for making the move away from Intel to custom silicon was to improve the experience, so these comparative details are going to be critically important. This is particularly true because of the generally disappointing performance of Arm-based Qualcomm and Microsoft chips in Windows on Arm PCs like the Surface Pro X. The key question will be if Apple is able to overcome some of the limitations and truly beat Intel-level performance, while simultaneously offering significantly better battery life. It’s an extremely challenging task but one that Apple clearly laid out as its goal.
There are also many unanswered questions about the ability to pair these new chips with external GPUs, such as the AMD Radeon parts Apple currently offers in certain Macs, or any other companion chips, such as 5G modems. While Apple currently uses Qualcomm modems for the iPhone and certain iPads, the company is known to be working on its own modems, and it’s not clear if those will be available in time for the launch of a 5G-equipped Macbook (should they choose to do so). As for graphics, Apple only uses its own GPU designs for its other custom parts for iPhones and iPads, but some computing applications require more graphics horsepower than those devices do, so it will be interesting to see if Apple offers the option to pair its new Mac-specific SOCs with external GPUs.
Finally, of course, there is the question of software. To get the best possible performance on any platform, you need to have software developers write applications that are native to the instruction sets being used. Because that can take a while, you also have to have a means to run existing software (that is, designed for Intel-based Macs) on the new chips via emulation. Ironically, Apple has chosen to use the exact same playbook to transition away from Intel processors that it used to transition into Intel processors. In fact, it’s even using the same names (with the addition of a version 2) for the core technologies: Universal Binaries 2 are combined applications that run on both Intel CPUs and the new Apple custom silicon chips and Rosetta 2 is the software used to emulate Intel instructions. This time around Apple also added some virtualization capabilities and demoed the ability to run Linux in a virtualized container. However, interestingly, there was no discussion of Windows running on the new Mac. Presumably all the work that Microsoft and its partners have done to bring Windows to Arm-based CPUs should port over fairly easily to Apple designs as well, but the details on this are not clear just yet.
To the company’s credit, Apple did an impressive job when it created this playbook to move from PowerPC-based chips to Intel, so here’s hoping the same strategy works the other way around. While Apple made it seem like it was a fairly trivial task to shift from x86-based instructions to Arm, if you use its Xcode development environment, history strongly suggests that the transition can be a bit daunting for some developers. To their credit, however, Apple did show functioning demos of critical Microsoft Office, Adobe Creative Cloud, and Apple professional apps running natively in the new environment. One concern Apple didn’t address at all was hardware device drivers. That was a key challenge for early Arm on Windows devices, so it will be interesting to see how Apple does with this.
One nice advantage that Apple and its developers gain by moving over to the same Arm-based architectures that it uses for the iPhone and iPad is that iOS and iPadOS applications should easily run on these new Macs—a point Apple was eager to make. As exciting as that first sounds, however, there is that detail of a lack of a touch screen on any existing Mac. Imagine trying to use a mouse with your iPhone, and you can see how initial enthusiasm for this capability may dampen, unless Apple chooses to finally allow touchscreens on Macs. We shall see.
The last point to make regarding all of these developments is that Apple ultimately chose to move to Arm to gain complete control over the Mac experience. As good as Intel’s processors have been, Apple has shown with its other devices that it likes to own the complete vertical technology stack, and the only way to do that was to design the CPU as well. It’s the last critical piece of the puzzle for Apple’s strategy to control its own destiny.
Regardless of that reasoning, however, it’s clear that both Apple’s decision and the supercomputing win mentioned earlier provide a great deal of credence to Arm’s efforts. At the same time, it arguably puts even more pressure on Arm to continue its pace of innovations. For a company that so few people really appreciate and understand, it’s great to see how far and how wide Arm has pushed the boundaries of computing. Now let’s see how they continue to evolve.