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Welcome to CRIU, a project to implement checkpoint/restore functionality for Linux in userspace.
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__NOTOC__
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<big>Welcome to CRIU, a project to implement checkpoint/restore functionality for Linux.
  
== This wiki ==
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Checkpoint/Restore In Userspace, or CRIU (pronounced kree-oo, IPA: /krɪʊ/, Russian: криу), is a Linux software. It can freeze a running container (or an individual application) and checkpoint its state to disk. The data saved can be used to restore the application and run it exactly as it was during the time of the freeze. Using this functionality, application or container live migration, snapshots, remote debugging, and [[usage scenarios|many other things]] are now possible.
  
;[[CR_tools | CR tools]]
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CRIU started as a project of Virtuozzo, and grew with the tremendous help from the [[community]]. It is currently used by (integrated into) OpenVZ, [[LXC]]/LXD, [[Docker]], Podman, and [[Integration|other software]], and [[packages|packaged for many Linux distributions]].
: Main checkpoint/restore utility
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{{Like}}
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<br clear="both">
  
;[[ZDTM_Test_Suite | ZDTM]]
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<div class="m_right">
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{{News block 2}}
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</div>
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<div class="m_left">
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== Using ==
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 +
<big>
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;Getting [[packages]] for your distribution
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: Or try manual [[installation]] to have CRIU on your system
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</big>
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;[[CLI]], [[RPC]] and [[C API]]
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: Three ways to start using the C/R functionality.  [[:Category:API|More info]] about APIs.
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 +
;[[Usage scenarios]]
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: Ideas how criu can be used (some are crazy indeed)
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;[[:Category:HOWTO]]
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: 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. Also a set of [[asciinema]] records for real-life examples.
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;[https://www.criu.org/index.php?title=FAQ FAQ] & [[When C/R fails]]
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: A sort of troubleshooting guide
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;[[What can change after C/R]]
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: CRIU cannot (yet) save and restore every single bit of tasks' state. This page describes what bits visible through standard kernel API are such.
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;[[What cannot be checkpointed]]
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: What an application could do to make CRIU refuse to dump it.
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 +
;[[Contacts]]
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: Ways to communicate with CRIU community
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</div>
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<div class="m_center">
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== Developing ==
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If you're interested in CRIU development, please subscribe to the criu mailing list: https://lists.openvz.org/mailman/listinfo/criu
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 +
;[[Images]]
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: Description of image files format
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 +
;[[Plugins]]
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: CRIU can call plugins provided by people
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 +
;[[Upstream kernel commits]]
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: Mainline kernel commits tracker
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 +
;[[Recent commits]]
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: CRIU tool repository commits
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 +
;[[Manpages]]
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: Kernel's manpages commits tracker
 +
 
 +
;[[ZDTM Test Suite]]
 
: Zero downtime test suite
 
: Zero downtime test suite
  
;[[Todo | TODO]]
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;[[Todo|TODO]]
 
: Current TODO list
 
: Current TODO list
  
;[[Commits | Commits]]
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;[[User namespace]]
: Mainline kernel commits tracker
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: Implementing user namespace support
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 +
;[[Postulates]]
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: What to keep in mind when writing new code
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 +
;[https://coveralls.io/github/checkpoint-restore/criu Code coverage results]
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: Shows how zdtm run covers the criu code paths
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;[[How to submit patches]]
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:
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</div>
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<br clear="both">
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<div class="m_left">
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== Under the hood ==
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* [[Checkpoint/Restore]]
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* [[:Category:Under the hood]]
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* [[:Category:Network]]
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* [[:Category:Files]]
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* [[:Category:Memory]]
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* [[Pending signals]]
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* [[Stages of restoring]]
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* [[Code blobs]]
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* [[Comparison to other CR projects]]
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</div>
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<div class="m_center">
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== External links ==
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{{:Articles}}
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</div>
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<div class="m_right">
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== Misc ==
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* [[Academic Research]]
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* [[Podcasts]] and other audio/video interviews
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* Project [[history]]
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* [[Logo]] description
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* [[Events]]
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* [[CRIU acronym fun]]
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</div>

Latest revision as of 13:03, 31 December 2023

Download
Tarball: criu-3.19.tar.gz
Version: 3.19 "Bronze Peacock"
Released: 27 Nov 2023
GIT tag: v3.19
InstallationUsage
Releases
3.19.jpg

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

Checkpoint/Restore In Userspace, or CRIU (pronounced kree-oo, IPA: /krɪʊ/, Russian: криу), is a Linux software. It can freeze a running container (or an individual application) and checkpoint its state to disk. The data saved can be used to restore the application and run it exactly as it was during the time of the freeze. Using this functionality, application or container live migration, snapshots, remote debugging, and many other things are now possible.

CRIU started as a project of Virtuozzo, and grew with the tremendous help from the community. It is currently used by (integrated into) OpenVZ, LXC/LXD, Docker, Podman, and other software, and packaged for many Linux distributions.


Using

Getting packages for your distribution
Or try manual installation to have CRIU on your system

CLI, RPC and C API
Three ways to start using the C/R functionality. More info about APIs.
Usage scenarios
Ideas how criu can be used (some are crazy indeed)
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. Also a set of asciinema records for real-life examples.
FAQ & When C/R fails
A sort of troubleshooting guide
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
What an application could do to make CRIU refuse to dump it.
Contacts
Ways to communicate with CRIU community

Developing

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

Images
Description of image files format
Plugins
CRIU can call plugins provided by people
Upstream kernel commits
Mainline kernel commits tracker
Recent commits
CRIU tool repository commits
Manpages
Kernel's manpages commits tracker
ZDTM Test Suite
Zero downtime test suite
TODO
Current TODO list
User namespace
Implementing user namespace support
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


Misc