To support the shipment of Apple Silicon Macs by the end of 2020, the company is sending developers a transition kit to help them prepare the code to run on the new architecture. The new case effectively fits an upgraded iPad Pro into a mini Mac case. This is why.
What is a computer?
Many of us assumed, however, that the latest Apple SoCs used in iPhones and iPad Pro would have to be significantly overhauled to power even the most basic MacBooks, and that Apple’s high-end desktop Macs could fully adhere to the processors. Intel. Surely the benchmarks showing that Apple’s A12Z is faster than most PC laptops was a kind of marketing hoax!
However, the more we learn about Apple’s existing SoCs, and the effort of Apple Silicon as a whole, the more confidence we have that Apple is already outperforming Intel in many ways. The idea that Apple’s custom silicon can only handle “mobile” workloads is the same kind of derogatory assumption that fueled the dismissive notion that iPads were just “media-consuming devices” and not “real” at some point. level.
Now that Apple has completed work to move macOS Big Sur and all of its own applications to run on Apple Silicon, effectively on an arm64 CPU, but with support for Apple’s GPU, Neural Engine, and all other components built into its SoC custom: it is indeed possible to host the Mac desktop on an iPad. But there is a catch.
iPad Pro tucked into a Mac mini case
The iPad is designed to be lightweight and slim and have an all-day battery life. One of the things that contributes to this highly mobile efficiency in form and function is the ultra-conservative use of RAM in its iPadOS, which it inherited from iOS. The less RAM the system needs, the less RAM Apple can include in the design. Fewer RAM chips in the device directly result in lower battery consumption. We used to point this out and once had a lot of criticism about it, but even Microsoft came out and agreed that “more RAM” was not always a good thing, particularly on a mobile device.
In fact, the reality of RAM power consumption was the main reason why Apple made a series of “brave” engineering decisions that resulted in iOS needing considerably less RAM than Android, Windows or Mac. The downside is that the Low RAM consumption also resulted in limitations on the number of applications that could run at once, or remain in the background, among other things. That is why Apple never positioned the iPad as a complete “no obligation” PC replacement. Real engineering requires decisive commitment.
Apple radically optimized iOS for mobility and longer battery life, leading to decisions that were once controversial. However, in hindsight, the use of ultra-conservative RAM on iOS was absolutely the right decision and made it incredibly difficult for Android or Windows licensees to match the performance and energy efficiency of iPhones and iPads. Less was literally more.
Some Macs are also light and thin and boast longer battery life, but even Apple’s MacBook Air sets its lower RAM limit at 8GB, and really wants it to command 16GB. A Mac mini will also allow you to order 8GB, but it does provide expansion slots that allow you to install 16GB, 32GB, or even 64GB. In contrast, Apple’s sleeker iPad Pro 2020 comes with just 6GB or RAM, with no expansion option. Older iPads shipped with 4GB or less. Apple’s iPad marketing pages don’t comment on how much RAM they include.
While iOS is desperately conservative on RAM, macOS generally accumulates as much RAM as you can. Beyond exploiting the RAM chips it installs, macOS also offers even more space by generously swapping out everything you don’t immediately need in RAM to the virtual memory backup store on your storage device, and then paging it again as appropriate. necessary. iOS also has virtual memory, but it doesn’t have a backup store. When the system runs out of RAM, it tells applications to free up space. If they don’t do it fast enough, they end. This is a radical difference in operation. Paging data from RAM to disk and vice versa consumes a lot of energy and slows down the system. That makes sense on a conventional computer, but not on a mobile device.
So while Apple has done the work of translating all of their macOS Big Sur to run on the Apple Silicon architecture of their iPads, the hardware on the table is not optimized to run macOS. The solution is quite simple: add more RAM. Apple is shipping the developer transition kit with 16GB of RAM, which is convenient for a Mac but would be devastating for an iPad’s battery.
USB 3.2 Type C is iPad Pro connectivity
Apple also detailed that its developer transition kit provides USB 3 connectivity through USB-C, as well as legacy USB-A and HDMI ports. This looks a bit like a Mac mini, but it’s really iPad Pro connectivity. The new Mac minis support Thunderbolt 3, which can control up to four 4K DisplayPort displays and compatible devices like RAID storage and eGPU expansion. Thunderbolt 3 is an Intel specification that works effectively as a cabled PCIe slot. Thunderbolt 3 connectivity support requires an Intel controller chip.
Most iOS devices only support USB 2, as well as a single 1080p HDMI video output, USB storage, and networking, all through Apple’s proprietary Lightning port with a dongle or special cable. Newer iPad Pro models have a USB C port that can handle the fastest USB 3 specification and up to 4K video output using a USB-C DisplayPort monitor, provided the display does not require Thunderbolt 3.
This makes it quite clear that the developer transition kit is not a Mac mini equipped with an Apple Silicon SoC, but rather an iPad Pro logic board connected to multiple USB, Ethernet and HDMI ports for added convenience. It has the same Bluetooth 5.0 and 802.11ac WiFi, and can connect to an SSD for storage via USB-C.
In several WWDC videos, Apple demonstrated what appears to be the developer transition kit running a 6K Pro Display XDR. Of course, no one would buy a 6K display and run it on a 4K iPad Pro, because it would be ridiculously expensive and wouldn’t actually work, nor would it make any sense. But Apple could either be using a custom Apple Silicon Mac prototype or simply use its sleek display as an accessory or hacked to support low-resolution USB-C video output. Don’t try this at home because it won’t work.
By the time Apple Silicon Macs begins shipping, the driver chips for the new USB 4 specification may be ready. Effectively, it makes Thunderbolt 3 connectivity part of the USB specification and eliminates the need to have Intel’s proprietary driver to support Thunderbolt 3 speeds.
That means Apple could add USB 4 support to its upcoming SoCs, and move both Apple Silicon Macs and the rest of its Lighting iOS and iPad lineup to USB-C ports, possibly all with Thunderbolt 3 speeds.
Still a no to convergence
Taken together, Apple’s details at WWDC demonstrate how the company’s Mac and iOS platforms can continue to pollinate as they increasingly share common code, including Catalyst apps that harmonize cross-platform functionality; richer development tools, such as Swift UI, which makes it easier to develop visually harmonious but platform-optimized applications; and, of course, more of the same common silicon.
However, this does not mean that Apple platforms are converging. The Mac is still optimized to run on a conventional desktop computer, powered primarily by a precise keyboard and pointer instead of touchscreens. There is no evidence that Apple is evaluating a change to turn its Mac displays into touchscreens, for example. That also indicates that Apple Pencil won’t be coming to Mac soon, or that MacBook screens will start to pull apart to become a strangely shaped tablet, just because everyone else is testing it.
Apple has expanded iPad Pro use cases by adding new keyboard options and support for a new touchpad, point-based integration with a touch interface. But there are also plenty of Mac features that don’t need to hit iPad, and they would actually erode their value in terms of portability, simplicity, and power efficiency.
The known unknowns
The other major conclusion is that Apple’s existing custom silicon has been purposely optimized for iOS and iPadOS, so we still don’t have a full understanding of how well the current A12Z will perform when given significantly more memory and an operating system. totally different adjusted to do very well. different work, without the need to conserve battery power so strictly. It certainly seems that without the limitations of the iPad Pro, Apple Silicon is already more powerful than we expected.
That’s particularly true because iOS is also highly optimized for single-core performance, specifically to offer a responsive user interface, despite the eight CPU cores available on the existing A12Z. Inside a connected desktop box, macOS has the ability to activate all four performance cores at once and drive them at full speed. Potentially it could even light up all eight, with advanced thread management that prioritizes scheduling to deliver a blazingly fast user interface while you’re using it, or the ability to populate numbers when you’re waiting for a processor-intensive task to complete, with lower priority tasks in the core efficiency groups.
And beyond the developer transition kit, the first Apple Silicon Macs to hit the market could offer even greater gains as they move toward the next generation of SoCs that take advantage of additional optimizations to specifically meet the needs of macOS. It is even possible that some Mac models incorporate multiple SoCs to maximize the available cores and offer more powerful graphics. Apple’s Mac Pro already combines two AMD GPUs along similar lines.
Future Apple Intel Macs can also transition from the existing T2 stub chip to incorporating a full Apple SoC to provide them access to resources including Apple’s GPU, Neural Engine, and other features. It might even be cheaper to mass-produce a high-performance SoC in massive quantities instead of designing a series of custom chips that are only used in a few million Macs.
Much remains to be discovered, but things are getting interesting.