docker container update
Description | Update configuration of one or more containers |
---|---|
Usage | docker container update [OPTIONS] CONTAINER [CONTAINER...] |
Aliases | docker update |
Description
The docker update
command dynamically updates container configuration.
You can use this command to prevent containers from consuming too many
resources from their Docker host. With a single command, you can place
limits on a single container or on many. To specify more than one container,
provide space-separated list of container names or IDs.
With the exception of the --kernel-memory
option, you can specify these
options on a running or a stopped container. On kernel version older than
4.6, you can only update --kernel-memory
on a stopped container or on
a running container with kernel memory initialized.
Warning
The
docker update
anddocker container update
commands are not supported for Windows containers.
Options
Option | Default | Description |
---|---|---|
--blkio-weight | Block IO (relative weight), between 10 and 1000, or 0 to disable (default 0) | |
--cpu-period | Limit CPU CFS (Completely Fair Scheduler) period | |
--cpu-quota | Limit CPU CFS (Completely Fair Scheduler) quota | |
--cpu-rt-period | API 1.25+ Limit the CPU real-time period in microseconds | |
--cpu-rt-runtime | API 1.25+ Limit the CPU real-time runtime in microseconds | |
-c, --cpu-shares | CPU shares (relative weight) | |
--cpus | API 1.29+ Number of CPUs | |
--cpuset-cpus | CPUs in which to allow execution (0-3, 0,1) | |
--cpuset-mems | MEMs in which to allow execution (0-3, 0,1) | |
-m, --memory | Memory limit | |
--memory-reservation | Memory soft limit | |
--memory-swap | Swap limit equal to memory plus swap: -1 to enable unlimited swap | |
--pids-limit | API 1.40+ Tune container pids limit (set -1 for unlimited) | |
--restart | Restart policy to apply when a container exits |
Examples
The following sections illustrate ways to use this command.
Update a container's cpu-shares (--cpu-shares)
To limit a container's cpu-shares to 512, first identify the container
name or ID. You can use docker ps
to find these values. You can also
use the ID returned from the docker run
command. Then, do the following:
$ docker update --cpu-shares 512 abebf7571666
Update a container with cpu-shares and memory (-m, --memory)
To update multiple resource configurations for multiple containers:
$ docker update --cpu-shares 512 -m 300M abebf7571666 hopeful_morse
Update a container's kernel memory constraints (--kernel-memory)
You can update a container's kernel memory limit using the --kernel-memory
option. On kernel version older than 4.6, this option can be updated on a
running container only if the container was started with --kernel-memory
.
If the container was started without --kernel-memory
you need to stop
the container before updating kernel memory.
Note
The
--kernel-memory
option has been deprecated since Docker 20.10.
For example, if you started a container with this command:
$ docker run -dit --name test --kernel-memory 50M ubuntu bash
You can update kernel memory while the container is running:
$ docker update --kernel-memory 80M test
If you started a container without kernel memory initialized:
$ docker run -dit --name test2 --memory 300M ubuntu bash
Update kernel memory of running container test2
will fail. You need to stop
the container before updating the --kernel-memory
setting. The next time you
start it, the container uses the new value.
Kernel version newer than (include) 4.6 does not have this limitation, you
can use --kernel-memory
the same way as other options.
Update a container's restart policy (--restart)
You can change a container's restart policy on a running container. The new
restart policy takes effect instantly after you run docker update
on a
container.
To update restart policy for one or more containers:
$ docker update --restart=on-failure:3 abebf7571666 hopeful_morse
Note that if the container is started with --rm
flag, you cannot update the restart
policy for it. The AutoRemove
and RestartPolicy
are mutually exclusive for the
container.