RISC-V vs. ARM: Who wins in 8 categories?

What was RISC-V again?

In the previous blog post, we delved into the details of RISC-V, an open-source instruction set architecture (ISA) that gained significant attention for its simplicity, modularity, and versatility. To summarize, RISC-V is open-source, which has led to widespread adoption, enabling companies and individuals to create their own RISC-V processors, tools, and systems. Additionally, RISC-V follows a modular structure, allowing for customizations and extensions based on specific application requirements.

What is ARM?

ARM, which stands for Advanced RISC Machines, reigns as a dominant instruction set architecture (ISA) renowned for its energy efficiency and high-performance capabilities. Unlike RISC-V, ARM is not open-source; instead, it has a rich history dating back to its inception in 1983. The widespread adoption of ARM processors spans a wide array of devices, ranging from smartphones and tablets to embedded systems, servers, and supercomputers. The allure of ARM lies in its exceptional power efficiency, which makes it an ideal choice for battery-powered devices, and its scalability, catering to diverse application domains with varying performance requirements.

Why compare RISC-V and ARM?

Comparing ARM and RISC-V is essential due to their prominence and widespread adoption in the world of computing. Both architectures have made significant impacts on various industries, but they have distinct design philosophies, licensing models, and ecosystems. While ARM has long dominated the mobile and embedded markets, RISC-V has emerged as a formidable challenger, gaining traction for its open-source nature and modularity.

By understanding the strengths and weaknesses of each architecture, developers, businesses, and enthusiasts can make informed decisions about which one suits their specific needs better. Furthermore, this comparison can offer valuable insights into the future trajectory of processor design and the potential disruption caused by open-source architectures like RISC-V in an industry that has been traditionally dominated by proprietary solutions like ARM. Overall, a comparative analysis between ARM and RISC-V promises to provide a comprehensive understanding of two prominent ISA giants and their implications for the future of computing.

Round 1: Vendor Independence

With RISC-V, developers gain autonomy from vendor constraints, empowering them to cherry-pick hardware and software providers that best suit their preferences. This liberation from vendor lock-in liberates customers to adopt the most fitting solutions tailored to their unique requirements, avoiding the limitations of a sole source. Additionally, RISC-V's open-source paradigm ensures a stable, sustainable future, guaranteeing continued availability and support over extended timeframes. Companies are encouraged to actively engage with the RISC-V community, contributing to the shared pool of knowledge and innovations, to fully harness the advantages of open sources. If companies fail to participate in the open-source development of RISC-V, they risk limiting the growth of the ecosystem.

Round 2: Cost-effectiveness

The open-source aspect of RISC-V not only ensures vendor independence but also plays a pivotal role in cutting manufacturing costs as it removes the burden of licensing fees. Moreover, the economic advantages of RISC-V extend to its reduced instruction set design, which simplifies the processor's development, verification, and manufacturing procedures, ultimately leading to the cost-effective production of RISC-V processors.

Round 3: Support and Liability

With its proprietary nature, ARM enjoys full support and liability coverage under ARM Holdings. Conversely, RISC-V's open-source approach lacks a centralized support system, entrusting support and liability responsibilities to individual implementers and the community. Nevertheless, open-source projects with a strong fan base often witness exceptional customer support, and the rapidly growing popularity of RISC-V suggests that this trend might eventually manifest in this technology as well.

Round 4: Market Share

As of the present time, ARM retains its dominance as the more prevalent instruction set architecture (ISA) compared to RISC-V. The legacy of ARM's existence in the computing industry over several decades has led to its widespread use. Backed by a mature ecosystem, robust software support, and a versatile range of processor cores, ARM remains the preferred choice for numerous companies and developers globally. While RISC-V's growing popularity can be attributed to its open-source nature and customization capabilities, it has not come close to the same level of market penetration as ARM. Remarkably, there are currently over 10 billion deployed RISC-V cores, but ARM still holds an astonishing 95% market share on smartphones.

Round 5: Customizability and Flexibility

One of the standout advantages of RISC-V lies in its remarkable customizability and flexibility. As an open-source instruction set architecture (ISA), RISC-V enables developers to tailor the design to their specific needs, fostering innovation and specialization in diverse applications. Unlike proprietary ISAs, RISC-V allows users to create customized instruction extensions and adapt the architecture to suit particular use cases, thus optimizing performance and power efficiency. This level of flexibility empowers companies, researchers, and hobbyists to explore new possibilities and create cutting-edge solutions, making RISC-V an ideal choice for industries seeking tailor-made processors and driving advancements across various domains. The open-source nature of RISC-V ensures that its customizability and adaptability will continue to evolve, offering endless potential for future innovations and emerging technologies.

Round 6: Hardware Security

In critical applications such as military operations or the finance sector, hardware security is of utmost importance. Relying on ARM's security implementations entails placing trust in their designs and the measures provided by ARM Holdings and partners. On the other hand, RISC-V's open-source nature allows companies and developers to assume direct control over security. Transparency and accessibility enable organizations to scrutinize the RISC-V architecture, identify vulnerabilities, and customize security measures to their precise requirements. 

Round 7: Rapid Prototyping

On one hand, the open-source nature of RISC-V provides a unique advantage for researchers and startups in their early development phases. The absence of licensing fees and the freedom to modify the architecture make it an attractive option for those seeking cost-effective exploration and experimentation. On the other hand, ARM offers comprehensive development kits specifically designed for companies aiming to streamline the prototyping process. Equipped with indispensable tools, documentation, and support, these kits enable developers to fast-track their projects with a structured framework, potentially minimizing associated costs. In essence, the choice between RISC-V and ARM for rapid prototyping hinges strongly on the unique requirements and resources of the development endeavor.

Round 8: Development Agility

RISC-V's open-source foundation not only fuels the rapid expansion of its application library but also empowers agile responses to emerging issues and security vulnerabilities. Its accessible architecture enables developers to promptly address specific challenges, leading to swift updates and tailored solutions. The collaborative community environment fosters a collective approach to problem-solving, facilitating rapid responses to security threats and continuous enhancements to the software library. In contrast, ARM's proprietary nature may hinder quick adaptability, as updates rely solely on the company's development efforts.

Scoreboard: 

Now, we proudly present the champions of each category, mindful of the dynamic nature of software competitions where outcomes can shift with each new product in the market:

Feature	RISC-V	ARM
Vendor Independence	➕
Cost-effectiveness	➕
Support und Liability		➕
Market Share		➕
Customizability and Flexibility	➕
Hardware Security	➕	➕
Rapid Prototyping	➕	➕
Development Agility	➕
Summarize	6	4

 Who won the fight?

In the high-stakes arena of RISC-V versus ARM, RISC-V emerges as a powerhouse driven by its open-source nature. The vendor independence it grants companies ensures long-term stability and brings compelling economic reasons to choose RISC-V over proprietary alternatives. Furthermore, the transparent architecture fosters an extensive community that thrives on support and collaboration, akin to examples like the Linux community, which competes with proprietary giants like Microsoft Windows, or Mozilla Firefox, which challenges the market share of Chrome. However, challenges lie ahead, with ARM's dominant market share, especially in the mobile domain. RISC-V will require time and increasing support from companies and developers worldwide to secure a significant place at the table. The aspect of performance poses another significant hurdle, with ARM's decades of development and fine-tuning bestowing it with an edge that RISC-V must strive to overcome. Undeterred, RISC-V stands ready to embark on this grand adventure, confident that as it matures, its unmatched customizability and flexibility will unveil unparalleled opportunities, reshaping the very essence of computing.

What does the next fight look like?

Some of you may have noticed, that some of the most important categories were missing in this article, like performance, speed, power consumption, latency, and more. Those attributes depend much more on the specific use case than the others do. This is why we first laid the focus on more general questions. For the more specific ones, we'll be putting RISC-V and ARM in these categories to the test. Our PRTG Multi-platform probe will be put through its paces on SciFive VisionFive2 and Raspberry PIEs, yielding valuable insights into these cutting-edge technologies. Stay tuned to this blog for a fascinating exploration of how these processors stack up in real-world scenarios. Get ready for an exciting hardware-based comparison in our upcoming article!

Missed the last article on RISC-V?