Understanding Huawei’s HarmonyOS: Structure, Kernels, and Uniqueness
Huawei’s HarmonyOS (also known as Hongmeng OS in China) represents a new direction in operating system design, especially tailored for the era of IoT, smart devices, and distributed computing. In this blog post, we’ll explore HarmonyOS’s architecture, its unique multi-kernel design, and how it differs from traditional generalized operating systems.
🌐 What is HarmonyOS?
Launched by Huawei in 2019, HarmonyOS is a microkernel-based distributed operating system designed to run across multiple types of devices, including smartphones, smart TVs, tablets, wearables, IoT devices, and even vehicles. The vision behind HarmonyOS is to provide a unified user experience across diverse hardware platforms.
🧱 HarmonyOS Architecture Overview
HarmonyOS employs a modular architecture that supports flexible deployment. Here’s a high-level breakdown:
- Application Layer: Where apps run, using the DevEco Studio and Huawei’s APIs.
- Framework Layer: Provides essential services to applications (UI, media, security).
- System Service Layer: Manages communication, distributed data, and scheduling.
- Kernel Layer: The heart of HarmonyOS — and where it gets particularly interesting.
🔧 The Multi-Kernel Design
Unlike most traditional operating systems that use a monolithic kernel or a single microkernel, HarmonyOS features a multi-kernel architecture. This design allows it to use different kernels on different devices, depending on performance needs and hardware characteristics.
📌 Kernels Used in HarmonyOS:
- LiteOS:
- A real-time operating system (RTOS) developed by Huawei.
- Used in lightweight IoT devices like smart sensors and wearables.
- Offers low power consumption and fast response times.
- Linux Kernel:
- Used in more resource-rich devices like smartphones and tablets.
- Provides broad compatibility with existing Linux software and development tools.
- Harmony Microkernel:
- A custom-designed microkernel focused on security and reliability.
- Used in critical system components, providing IPC (Inter-Process Communication), thread scheduling, and memory management.
🔄 How it can support Multiple Kernels?
🧩 Kernel Abstraction Layer: The Glue Behind Multi-Kernel Support
At the heart of HarmonyOS’s flexibility lies the Kernel Abstraction Layer (KAL). This layer sits above the actual kernels and acts as a unifying interface for the rest of the operating system.
🛠 What Does KAL Do?
- Abstracts Kernel Differences: It hides the implementation details of different kernels (Linux, LiteOS, Harmony Microkernel) from upper layers.
- Provides Unified APIs: Developers and system services use consistent APIs, regardless of the underlying kernel.
- Enables Device Versatility: HarmonyOS can be deployed across devices with vastly different hardware and performance requirements.
Because of KAL, HarmonyOS can smartly map device capabilities to the appropriate kernel — all while maintaining a cohesive platform for apps and servic
🆚 Generalized Operating Systems vs. HarmonyOS
| Feature | Generalized OS (e.g. Android, Windows) | HarmonyOS |
|---|---|---|
| Kernel Structure | Typically monolithic or single kernel | Multi-kernel (microkernel + others) |
| Target Devices | Primarily single device type | Designed for multiple device types |
| Resource Optimization | Not always ideal for IoT | Tailored for various hardware sizes |
| Distributed Architecture | Limited | Built-in distributed computing |
| Developer Experience | Per device platform | Unified API across devices |
🔐 Security and Performance
The use of a microkernel brings higher security since it minimizes kernel space operations, reducing attack surfaces. Additionally, the deterministic latency and performance isolation features are ideal for real-time and critical applications.
