12 KiB
containerd
Containerd is a daemon to control runC, built for performance and density. Containerd leverages runC advanced features such as seccomp and user namespace support as well as checkpoint and restore for cloning and live migration of containers.
Status
alpha
What does alpha, beta, etc mean?
- alpha - not feature complete
- beta - feature complete but needs testing
- prod ready - read for production
Docs
For more documentation on various subjects refer to the /docs directory in this repository.
Building
You will need to make sure that you have Go installed on your system and the containerd repository is cloned
in your $GOPATH. You will also need to make sure that you have all the dependencies cloned as well.
Currently, contributing to containerd is not for the first time devs as many dependencies are not vendored and
work is being completed at a high rate.
After that just run make and the binaries for the daemon and client will be localed in the bin/ directory.
Downloads
The easy way to test and use containerd is to view the releases page for binary downloads. We encourage everyone to use containerd this way until it is out of alpha status.
Performance
Starting 1000 containers concurrently runs at 126-140 containers per second.
Overall start times:
[containerd] 2015/12/04 15:00:54 count: 1000
[containerd] 2015/12/04 14:59:54 min: 23ms
[containerd] 2015/12/04 14:59:54 max: 355ms
[containerd] 2015/12/04 14:59:54 mean: 78ms
[containerd] 2015/12/04 14:59:54 stddev: 34ms
[containerd] 2015/12/04 14:59:54 median: 73ms
[containerd] 2015/12/04 14:59:54 75%: 91ms
[containerd] 2015/12/04 14:59:54 95%: 123ms
[containerd] 2015/12/04 14:59:54 99%: 287ms
[containerd] 2015/12/04 14:59:54 99.9%: 355ms
Telemetry
Currently containerd only outputs metrics to stdout but will support dumping to various backends in the future.
[containerd] 2015/12/16 11:48:28 timer container-start-time
[containerd] 2015/12/16 11:48:28 count: 22
[containerd] 2015/12/16 11:48:28 min: 25425883
[containerd] 2015/12/16 11:48:28 max: 113077691
[containerd] 2015/12/16 11:48:28 mean: 68386923.27
[containerd] 2015/12/16 11:48:28 stddev: 20928453.26
[containerd] 2015/12/16 11:48:28 median: 65489003.50
[containerd] 2015/12/16 11:48:28 75%: 82393210.50
[containerd] 2015/12/16 11:48:28 95%: 112267814.75
[containerd] 2015/12/16 11:48:28 99%: 113077691.00
[containerd] 2015/12/16 11:48:28 99.9%: 113077691.00
[containerd] 2015/12/16 11:48:28 1-min rate: 0.00
[containerd] 2015/12/16 11:48:28 5-min rate: 0.01
[containerd] 2015/12/16 11:48:28 15-min rate: 0.01
[containerd] 2015/12/16 11:48:28 mean rate: 0.03
[containerd] 2015/12/16 11:48:28 counter containers
[containerd] 2015/12/16 11:48:28 count: 1
[containerd] 2015/12/16 11:48:28 counter events
[containerd] 2015/12/16 11:48:28 count: 87
[containerd] 2015/12/16 11:48:28 counter events-subscribers
[containerd] 2015/12/16 11:48:28 count: 2
[containerd] 2015/12/16 11:48:28 gauge goroutines
[containerd] 2015/12/16 11:48:28 value: 38
[containerd] 2015/12/16 11:48:28 gauge fds
[containerd] 2015/12/16 11:48:28 value: 18
Daemon options
$ containerd -h
NAME:
containerd - High performance container daemon
USAGE:
containerd [global options] command [command options] [arguments...]
VERSION:
0.0.4
AUTHOR(S):
@crosbymichael <crosbymichael@gmail.com>
COMMANDS:
help, h Shows a list of commands or help for one command
GLOBAL OPTIONS:
--id "deathstar" unique containerd id to identify the instance
--debug enable debug output in the logs
--state-dir "/run/containerd" runtime state directory
-c, --concurrency "10" set the concurrency level for tasks
--metrics-interval "1m0s" interval for flushing metrics to the store
--listen, -l "/run/containerd/containerd.sock" Address on which GRPC API will listen
--oom-notify enable oom notifications for containers
--help, -h show help
--version, -v print the version
Roadmap
The current roadmap and milestones for alpha and beta completion are in the github issues on this repository. Please refer to these issues for what is being worked on and completed for the various stages of development.
API
GRPC API
The API for containerd is with GRPC over a unix socket located at the default location of /run/containerd/containerd.sock.
At this time please refer to the proto at for the API methods and types.
There is a Go implementation and types checked into this repository but alternate language implementations can be created using the grpc and protoc toolchain.
containerd CLI
There is a default cli named ctr based on the GRPC api.
This cli will allow you to create and manage containers run with containerd.
NAME:
ctr - High performance container daemon controller
USAGE:
ctr [global options] command [command options] [arguments...]
VERSION:
0.0.4
AUTHOR(S):
@crosbymichael <crosbymichael@gmail.com>
COMMANDS:
checkpoints list all checkpoints
containers interact with running containers
events receive events from the containerd daemon
help, h Shows a list of commands or help for one command
GLOBAL OPTIONS:
--debug enable debug output in the logs
--address "/run/containerd/containerd.sock" address of GRPC API
--help, -h show help
--version, -v print the version
Listing containers
$ sudo ctr containers
ID PATH STATUS PID1
1 /containers/redis running 14063
19 /containers/redis running 14100
14 /containers/redis running 14117
4 /containers/redis running 14030
16 /containers/redis running 14061
3 /containers/redis running 14024
12 /containers/redis running 14097
10 /containers/redis running 14131
18 /containers/redis running 13977
13 /containers/redis running 13979
15 /containers/redis running 13998
5 /containers/redis running 14021
9 /containers/redis running 14075
6 /containers/redis running 14107
2 /containers/redis running 14135
11 /containers/redis running 13978
17 /containers/redis running 13989
8 /containers/redis running 14053
7 /containers/redis running 14022
0 /containers/redis running 14006
Starting a container
$ ctr containers start -h
NAME:
start - start a container
USAGE:
command start [command options] [arguments...]
OPTIONS:
--checkpoint, -c checkpoint to start the container from
--attach, -a connect to the stdio of the container
$ sudo ctr containers start redis /containers/redis
Kill a container's process
$ ctr containers kill -h
NAME:
kill - send a signal to a container or it's processes
USAGE:
command kill [command options] [arguments...]
OPTIONS:
--pid, -p "0" pid of the process to signal within the container
--signal, -s "15" signal to send to the container
Exec another process into a container
$ ctr containers exec -h
NAME:
exec - exec another process in an existing container
USAGE:
command exec [command options] [arguments...]
OPTIONS:
--id container id to add the process to
--attach, -a connect to the stdio of the container
--cwd current working directory for the process
--tty, -t create a terminal for the process
--env, -e [--env option --env option] environment variables for the process
--uid, -u "0" user id of the user for the process
--gid, -g "0" group id of the user for the process
Stats for a container
$ ctr containers stats -h
NAME:
stats - get stats for running container
USAGE:
command stats [arguments...]
List checkpoints
$ sudo ctr checkpoints redis
NAME TCP UNIX SOCKETS SHELL
test false false false
test2 false false false
Create a new checkpoint
$ ctr checkpoints create -h
NAME:
create - create a new checkpoint for the container
USAGE:
command create [command options] [arguments...]
OPTIONS:
--tcp persist open tcp connections
--unix-sockets perist unix sockets
--exit exit the container after the checkpoint completes successfully
--shell checkpoint shell jobs
Get events
$ sudo ctr events
TYPE ID PID STATUS
exit redis 24761 0
License
Apache 2.0 found in the LICENSE file.
Sign your work
The sign-off is a simple line at the end of the explanation for the patch. Your signature certifies that you wrote the patch or otherwise have the right to pass it on as an open-source patch. The rules are pretty simple: if you can certify the below (from developercertificate.org):
Developer Certificate of Origin
Version 1.1
Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
660 York Street, Suite 102,
San Francisco, CA 94110 USA
Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.
Developer's Certificate of Origin 1.1
By making a contribution to this project, I certify that:
(a) The contribution was created in whole or in part by me and I
have the right to submit it under the open source license
indicated in the file; or
(b) The contribution is based upon previous work that, to the best
of my knowledge, is covered under an appropriate open source
license and I have the right under that license to submit that
work with modifications, whether created in whole or in part
by me, under the same open source license (unless I am
permitted to submit under a different license), as indicated
in the file; or
(c) The contribution was provided directly to me by some other
person who certified (a), (b) or (c) and I have not modified
it.
(d) I understand and agree that this project and the contribution
are public and that a record of the contribution (including all
personal information I submit with it, including my sign-off) is
maintained indefinitely and may be redistributed consistent with
this project or the open source license(s) involved.
Then you just add a line to every git commit message:
Signed-off-by: Joe Smith <joe.smith@email.com>
Use your real name (sorry, no pseudonyms or anonymous contributions.)
If you set your user.name and user.email git configs, you can sign your
commit automatically with git commit -s.