What is gVisor?
gVisor is an application kernel, written in Go, that implements a substantial portion of the Linux system call interface. It provides an additional layer of isolation between running applications and the host operating system.
Overview
gVisor is developed by Google and provides efficient defense-in-depth anywhere by implementing most Linux system calls in a memory-safe language (Go) and speaking directly to the host kernel through a limited set of calls.
Key Features
🛡️ Security
- Additional layer of isolation between applications and host OS
- Reduced attack surface with limited host system calls
- Memory-safe implementation in Go
🚀 Performance
- Lower overhead than traditional VMs
- Efficient resource utilization
- Fast startup times
🔧 Compatibility
- Implements most Linux system calls
- Works with existing container runtimes (Docker, containerd, Kubernetes)
- Supports most Linux applications without modification
🌐 Portability
- Platform-independent userspace kernel
- Runs on different host operating systems
- Multiple platform implementations (KVM, ptrace)
How gVisor Works
gVisor acts as a "guest kernel" running in userspace, intercepting and handling system calls from applications. Instead of allowing direct access to the host kernel, gVisor:
- Intercepts system calls from the application
- Implements the system call in Go userspace
- Makes limited, controlled calls to the host kernel when necessary
- Returns results back to the application
This approach provides strong isolation while maintaining compatibility.
Use Cases
Container Security
- Enhance container isolation beyond traditional namespaces and cgroups
- Run untrusted workloads safely
- Multi-tenant environments requiring strong isolation
Cloud Computing
- Serverless computing platforms
- Function-as-a-Service (FaaS) environments
- Microservices with enhanced security
Development & Testing
- Safe testing environments
- Sandboxed development workflows
- CI/CD pipeline isolation
Architecture Components
Sentry
The "kernel" that runs in userspace and implements Linux system calls.
Gofer
A file proxy that provides access to files, implementing the filesystem interface.
runsc
The runtime that integrates with container orchestrators like Docker and Kubernetes.
Comparison with Other Solutions
| Feature | gVisor | Traditional VMs | Standard Containers |
|---|---|---|---|
| Startup Time | Fast | Slow | Very Fast |
| Memory Overhead | Low | High | Very Low |
| Security Isolation | Strong | Very Strong | Moderate |
| Compatibility | High | Very High | Very High |
| Performance | Good | Moderate | Excellent |
Getting Started
Ready to try gVisor? Continue with the Installation Guide to set up gVisor on your system.
Resources
- Homepage: https://gvisor.dev
- Source Code: https://github.com/google/gvisor
- Documentation: https://gvisor.dev/docs/
- Community: GitHub Discussions