Download Tarball: criu-4.0.tar.gz Version: 4.0 "CRIUDA" Released: 20 Sep 2024 GIT tag: v4.0 Installation • Usage Releases

Welcome to CRIU, a project to implement checkpoint/restore functionality for Linux in userspace.

Checkpoint/Restore In Userspace, or CRIU (pronounced kree-oo, IPA: /krɪʊ/, Russian: криу), is a software tool for Linux operating system. Using this tool, you can freeze a running application (or part of it) and checkpoint it to a hard drive as a collection of files. You can then use the files to restore and run the application from the point it was frozen at. The distinctive feature of the CRIU project is that it is mainly implemented in user space.

http://static.openvz.org/criu_88x31.gif is a project of http://static.openvz.org/openvz_88x31.gif and is sponsored and supported by http://static.openvz.org/parallels_88x31.gif

Using

Installation

What to do to have CRIU on your system

CLI and RPC

Two ways to start using the C/R functionality

Usage scenarios

Ideas how criu can be used (some are crazy indeed)

What software is supported

Describes TODO list in higher level terms

Category:HOWTO

Collection of real world examples of how to use CRIU. Some are complex, some are not. HOW TO dump a simple loop might be the best one to start with.

What can change after C/R

CRIU cannot (yet) save and restore every single bit of tasks' state. This page describes what bits visible through standard kernel API are such.

What cannot be checkpointed

This article describes what application can do to make CRIU refuse to dump it. It can be used as some sort of troubleshooting guide. The article titled 'What cannot be restored' does not exist and will never be, as if something was dumped, it should be restored.

Developing

If you're interested in CRIU development, please subscribe to the criu mailing list: http://lists.openvz.org/mailman/listinfo/criu

Images

Description of image files format

Commits

Mainline kernel commits tracker

Manpages

Kernel's manpages commits tracker

ZDTM Test Suite

Zero downtime test suite

TODO

Current TODO list

Postulates

What to keep in mind when writing new code

Code coverage results

Shows how zdtm run covers the criu code paths

How to submit patches

Events LinuxDays 2024 13 Oct 2024, On the Edge of Tomorrow: Checkpoint/Restore in Containers Kubernetes Community Days Austria 09 Oct 2024, Forensic container checkpointing and analysis Linux Plumbers Conference 2024 18-20 Sep 2024, Containers and Checkpoint/Restore Microconference Other talks: * Userspace memory persistence over kexec * Checkpoint/Restore In eBPF (CRIB)

Under the hood

• Sockets
• Memory dumping and restoring
• Checkpoint/Restore
• TCP connection
• Files
• Pending signals
• Stages of restoring
• COW
• Code blobs
• Comparison to other CR projects
• Memory changes tracking

External links

• 2024-11-14, On-demand and Parallel Checkpoint/Restore for GPU Applications
• 2024-09-06, Live Migration of Multi-Container Kubernetes Pods in Multi-Cluster Serverless Edge Systems
• 2024-09-04, Towards Efficient End-to-End Encryption for Container Checkpointing Systems
• 2024-08-04, Custom Page Fault Handling With eBPF
• 2024-08-03, Software-based Live Migration for Containerized RDMA
• 2024-07-30, Packet Buffering to Minimize Service Downtime and Packet Loss During Redundancy Switchover
• 2024-07-30, Don't, Stop, Drop, Pause: Forensics of CONtainer CheckPOINTs (ConPoint)
• 2024-07-25, MDB-KCP: persistence framework of in-memory database with CRIU-based container checkpoint in Kubernetes
• 2024-07-23, Dapper: A Lightweight and Extensible Framework for Live Program State Rewriting

More external articles...

Other

• Project history
• Logo description
• Events
• Join the CRIU acronym fun