What is RISC-V and Why Has it Become Important for Java?

RISC stands for reduced instruction set computer, and V points to its fifth release in 2015. RISC-V is the new processor architecture to watch out for. Arm-based processors, which stayed among the most popular ones in recent years, may capture a significant share of the semiconductor market, and this is why.

Arm and RISC-V are a type of processor architecture. Another well-known processor architecture type is x86.

Arm and RISC-V chips are used by various industries, from tablets to servers, but initially, they targeted the embedded market. Their design specifics allow them to offer sufficient performance while keeping power consumption low.

RISC-V is a novel open source instruction set architecture (ISA) based on the reduced instruction set computer (RISC) model. The project started at the University of California, Berkeley and was taken over by the RISC-V Foundation in 2015.

Using the x86 and arm processors for hardware development implies high fees because you need to pay royalties to the providers of processor IP, making production expensive and delivering bureaucratic complications. The RISC-V project brought liberation in this sense, creating a new model based on the open-source approach, allowing users to use these processors free of charge. In short, RISC-V is getting more and more popular thanks to its improved design and open-source approach to its development.

RISC-V consists of a set of basic instructions. These instructions act as a communication bridge between hardware and software. RISC-V includes 47 instructions, and additional extensions can be added in a modular way. Thanks to that, RISC-V is smaller compared to x86 or ARM.

In contrast to other popular processors, RISC-V is open source, and therefore, anyone can design, manufacture and sell RISC-V chips and software. As such, RISC-V established new opportunities for modern computing devices, from mobile phones to supercomputers and even microchips for the space industry. Space industry technologies are very challenging as they operate in very different environmental factors. Consequently, the recent NASA announcement on selecting SiFive RISC-V as the core CPU for the high-performance spaceflight computing (HPSC) processor is a great example of the power of RISC-V architecture.

RISC-V belongs to so-called “disruptive technologies.” It removes drawbacks of older systems, eliminating complexity together with licensing fees,, as a result delivering new levels of software flexibility and performance and reducing costs of application development.

According to the RISC-V market report by SHD Group, RISC-V SoCs are forecasted to reach $92.7 billion by 2030, representing a 47% annual growth rate. So, we are still in the early stages of adaptation. Considering that RISC-V can be used as a key ingredient for anything from a smartphone chip to advanced processors for artificial intelligence, its market share could grow very quickly.

It should be noted that Asia is a step ahead in using RISC-V architecture today, with Huawei and Alibaba leading the game. But we also see increasing involvement from companies such as Google, IBM and others. At the same time, the early adoption of RISC-V has already caused a political debate on the microchip trade policy between the U.S. and China.

Java on RISC V

Java has always been at the top of the list for enterprise coding languages, and it is also one of the most widespread languages for embedded systems.

However, applying Java to embedded systems requires adapting it to their technical requirements, which is why Oracle and several OpenJDK vendors have created a special edition of Java for embedded systems. Java runtime for embedded should be compiled into the native ISA for the target hardware, supported by highly tailored, relatively small runtime packages, able to execute on multiple processors if needed for capacity expansion.

RISC-V presents a new type of hardware and needs an adapted version of Java too. So, the Java community initiated the RISC-V port, which was successfully integrated into JDK 19.

However, even with a port in place, you still need to build and test the JDK binary correctly to use it with RISC-V. Today, many OpenJDK vendors and Linux distributions look to offer packages for RISC-V, and gradually, most of the vendors will be delivering JDK packages adapted to RISC-V. But it is great to be among the first. BellSoft released Liberica JDK builds for Linux on RISC-V for JDK 21 LTS. BellSoft commits to supporting version 21 until 2032, providing users with all the benefits of an open source Java runtime from a leading OpenJDK contributor. This includes quarterly CPU and PSU updates and additional solutions for Java development. The RISC-V support in Liberica JDK comes with a Standard JDK flavor, offering three VMs: Server VM, Client VM and Minimal VM designed specifically for systems with lower performance so that your Java applications start up faster and utilize less memory.

OpenJDK and RISC-V are both open source projects; Liberica JDK is free for personal and commercial use. The BellSoft team is glad to continue contributing to the secure and easy development process of Java applications and allowing early access to evolving technologies.

RISC-V is changing the hardware manufacturing market and requires the closest attention from software developers too. RISC-V delivers a sustainable approach to development, removing unnecessary barriers, providing new levels of flexibility and scalability and, as a result, reducing the cost of chip production. RISC-V combined with correct application development practice can completely change the tech future.