Apple Inc. began the transition from Intel Core processors and x86 architecture to a new class of processors designed in-house based on the ARM architecture with the announcement of Apple Silicon for Macintosh computers during the Worldwide Developers Conference held on 22 June 2020. Nonetheless, the Apple M1 processor is the first-generation M series system on a chip or SoC launched in November 2020 alongside the introduction of the new models of the Mac Mini, MacBook Air, and MacBook Pro devices.
Several critics and enthusiasts welcomed the transition with skepticism due to the ongoing x86 versus ARM debate. However, with more M1-powered devices landing on the hands of software developers and tech reviewers, and in consideration of supporters of architecture based on reduced instruction set computer or RISC and ARM, the new Apple-designed chip proved to be a capable processor that can rival its Intel counterparts while boosting newfound excitement for future developments in the M series family of processors and Macintosh devices.
Architecture and Specifications of Apple M1
Process Node: Based on the 5nm manufacturing process node, the M1 is the second 5nm chip introduced by Apple, following the introduction of the the A14 Bionic chip for the iPhone 12 series. This new-generation chipmaking process node confers notable advantages.
CPU Cores: The Apple M1 has a multi-core processor with a specific 8-core configuration similar to the big.LITTLE heterogeneous computing feature of ARM. There are 4 high-performance cores called “Firestorm” and 4 energy-efficient cores called “Icestorm.”
GPU Cores: It also has an Apple-designed 7-core to 8-core integrated graphic processing unit. Hence, the processor has an integrated coprocessor designed to handle graphic performance. The entire hardware is capable of executing nearly 25000 threads at a time.
Neural Engine: There is also an integrated 16-core Neural Engine within the entire hardware system. This coprocessor equips the Apple M1 chip with a built-in machine learning capabilities that can execute 11 trillion operations per second.
Random Access Memory: It has a Unified Memory configuration using a 4266 MT/s LPDDR4X SDRAM shared by all of its components. Depending on the model of the Mac computer, the RAM is available at 8 GB and 16 GB configurations.
Other Components: There is an image signal processor built into the system for processing digital images, NVMe storage controller, Thunderbolt 4 controller, and the Secure Enclave coprocessor for hardware-based key management.
Features of the Apple M1 Processor
1. Based on RISC and ARM Architectures
A key feature of the Apple M1 processor is that it is based on reduced instruction set computer or RISC instruction set architecture and the more specific ARM microarchitecture. Hence, this Apple-designed chip inherits the advantages and applications of RISC and ARM to include using a lesser number of instruction formats, few numbers of instructions, and few addressing modes.
2. 5 Nanometer Process Technology
It is also the first processor built and used for personal computers using the 5 nanometer process technology. Apple managed to fit 16 billion transistors within a small area through this process. Fundamentally, chips with denser transistors are faster and more efficient. The 5 nanometer process is superior to the 7 nanometer and 10 nanometer processes.
3. Performance and Energy Management
The 4 high-efficiency Icestorm cores are designed for handling lightweight tasks to include basic office productivity and web browsing, while the other four high-performance Firestorm cores are activated for handling heavy workloads such as video editing and gaming. Through this heterogeneous computing feature, the chip can actively manage energy consumption based on performance or computing requirements and share the workload across all other cores.
4. Integrated Graphics Processor
Apple demonstrated its capability to design a processor not only with a multi-core CPU but also an integrated graphics processor or GPU. The multi-core unit can execute about 25,000 threads at a time. It can also process one trillion calculations per second. Note that this coprocessor does not only process graphics but also work alongside other processors within the chip.
5. Machine Learning Capabilities
Built within the chip are a 16-core Neural Engine and machine learning accelerators that work together with the CPU and GPU to equip a device with an Apple M1 chip with native machine learning capabilities. The engine can execute 11 trillion operations per second. Some examples of applications include smart and automated photo editing and video editing, active power management, and tailor-fitted user experience, among others.
6. Unified Memory Architecture
Take note that the Apple M1 processor is a system-on-a-chip or SoC. The entire hardware includes not only the main multi-core CPU but also a multi-core GPU, a multi-core Neural Engine, and an image signal processor, among others. These components can access the same data without copying in between multiple memory pools through a unified memory architecture, thus improving performance and power efficiency.
7. Compatibility with iOS and iPadOS Apps
Switching from x86 architecture to ARM architecture now allows Apple to enhance further its app and product ecosystem. An interesting feature of the Apple M1 chip is that it allows apps for iOS and iPadOS to run natively in macOS. These iPhone and iPad apps look, work, and behave like Mac apps. Note that iPhone and iPad are powered by ARM-based A series chips.
Advantages and Disadvantages of Apple M1
Remember that the M1 processer naturally inherits the advantages of RISC architecture and ARM architecture. Note that RISC processors are easier to design and deploy than those based on complex instruction set computer or CISC architecture. They also have lower per-chip costs because they require smaller components. Regarding the ARM architecture, ARM-based processors are known for having good performance per watt. They have been the preferred chip for use in battery-operated devices due to their energy efficiency. They also produce less heat than chips based on CISC and x86 architectures.
Aside from the inherent characteristics of RISC and advantages of ARM, another advantage of the Apple M1 processor is that it better aligns Mac devices and the macOS with iPhone and iPad devices, as well as the iOS and the iPadOS. Apps available for iPhone and iPad can now natively run in an M1-equipped Mac computer because these devices run on the same ARM-based chips. Users will benefit from cross-platform compatibility and availability of apps.
Initial reviews of M1-powered Mac Mini, MacBook Air, and MacBook Pro from software developers and tech enthusiasts revealed interesting results. Tests using Geekbench 5 showed that the 2020 MacBook Air with M1 outperformed the Intel-equipped 2020 MacBook Air and 2020 13-inch MacBook Pro in overall performance, integer, and floating point in a single core. In multiple cores, the same benchmark app showed that the M1-powered Air outperformed the Intel-based Air and Pro in all criteria.
Results of real-world and use case tests also highlighted the strengths of the Apple M1 chip over Intel processors. Rendering video from video editing software such as Final Cut Pro was faster than Intel-based Mac computers. Furthermore, true to the advantages of RISC and ARM architectures, numerous comparisons with Intel revealed that the M1 chip produced less heat while performing resource0intensive workloads or tasks.
Of course, despite the promises of this new Apple Silicon chip for Macintosh computers, there are some notable issues and drawbacks. For starters, there is an ongoing issue as regards app compatibility. Note that apps written for CISC and x86 architectures will not natively run on processors based on RISC and ARM. Apple has a workaround through Rosetta 2 that promises to translate and run x86-based apps on ARM-based M1 devices without hiccups.
The pressing problem with dependence on Rosetta 2 is that some app developers might not be able to transition faster or completely to ARM. Note that they need to rewrite their apps to allow compatibility. Furthermore, similar to the case of the first Rosetta released when Apple transition Macintosh from PowerPC processors to Intel processors in 2006, the translator software was discontinued after a few years. Compatibility issues with less-common apps are still possible. There are also doubts about possible Microsoft Windows virtualization.
Another notable disadvantage of the Apple M1 is that it is a system-on-a-chip. The entire hardware includes prebuilt components such as the CPU, GPU, Neural Engine, and shared RAM, among others. The problem with this is that M1-equipped Mac devices do not support expansion. More specifically, users cannot expand the RAM in the future. They cannot use an external GPU as well. In addition, the built-in controls in the chip only support one external display.