PusOS: Operating System for Next-Generation Fog Computing

Introduction

PusOS is a novel, lightweight operating system meticulously engineered to meet the demands of next-generation Fog Computing environments. It is built entirely in the kernel space on the open-source RISC-V instruction set, offering a highly efficient, secure, and transparent alternative to traditional monolithic operating systems such as Linux.

PusOS aims to unlock the full potential of distributed edge intelligence by delivering a streamlined, high-performance platform that brings computation, storage, and networking closer to end-users and IoT endpoints. The result: reduced latency, enhanced security, and improved quality of service.

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Key Features

• Kernel-Space-Only Execution
  Eliminates context switching overhead, enabling real-time response with minimal latency and predictable behavior.

• Lightweight Nanokernel Design
  Minimal footprint and customizable build aimed at constrained fog nodes and embedded deployments based on LittleKernel.

• RISC-V Architecture
  Fully open ISA support allowing complete hardware-software co-design and future extensibility.

• Integrated Networking Stack
  Lightweight TCP/UDP support with future plans for IoT protocols like CoAP, MQTT, and secure HTTP-based Cloud access.

• Optimized Flash Storage
  Uses LittleFS for robust and fault-tolerant operations on embedded flash media.

• Fault Tolerance & Self-Recovery
  Designed for high availability with self-healing capabilities after runtime crashes.

• Application Migration
  Supports transparent process migration between fog nodes for dynamic load balancing and resilience.

• Virtualization Support
  Enables secure, sandboxed execution environments for isolated tasks and services.

• Open Source and Modular
  Built for transparency, extensibility, and community contributions.

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Getting Started

These instructions will help you build and run PusOS on your local development environment using QEMU and a RISC-V toolchain.

Prerequisites

Make sure the following tools are installed on your system:

• QEMU (≥ 9.0.1) – RISC-V virtualization

  sudo apt install qemu-system-riscv64

• RISC-V GCC Toolchain (≥ 13.2.0) – For cross-compiling the kernel

  sudo apt install gcc-riscv64-linux-gnu

• Optional: Milis Linux as host OS for development
  (Any modern Linux distro should work.)

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Building PusOS

# 1- Download toolchain
scripts/download_toolchain.sh

# 2- Build kernel
make pus

# 3- Adjust network
sudo scripts/network_setup.sh

# 4- Create block device
scripts/block_create.sh

# 5- Boot system
scripts/qemu.sh build-pus/lk.elf

Tests

# 1- Download toolchain
scripts/download_toolchain.sh

# 2- Build kernel
make pus

# 3- Adjust network
sudo scripts/setup_network.py $node_count

# 4- Start Cluster
scripts/start_cluster.sh $node_count

# 5- Start [Pusctl](https://github.com/milisarge/pusctl)
./pusctl