From e2a6cf9fd573739451a40b38f4e438a71ef41709 Mon Sep 17 00:00:00 2001 From: Sebastiaan van Stijn Date: Tue, 12 Jul 2016 14:29:02 +0200 Subject: [PATCH] docs: cleanup docker update docs move the "kernel memory" examples to the "examples" section, and fix some formatting and grammar. Signed-off-by: Sebastiaan van Stijn --- docs/reference/commandline/update.md | 72 +++++++++++++++++----------- man/docker-update.1.md | 72 +++++++++++++++++----------- 2 files changed, 88 insertions(+), 56 deletions(-) diff --git a/docs/reference/commandline/update.md b/docs/reference/commandline/update.md index 7cd624c9d5..1b1365dedb 100644 --- a/docs/reference/commandline/update.md +++ b/docs/reference/commandline/update.md @@ -31,44 +31,25 @@ Options: ``` 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. +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` value, you can specify these +With the exception of the `--kernel-memory` option, you can specify these options on a running or a stopped container. You can only update `--kernel-memory` on a stopped container or on a running container with -kernel memory initialized. For example, if you started a container with -command: - - # docker run -ti --name test --kernel-memory 50M ubuntu bash - -You can update kernel memory of this running container: - - # docker update --kernel-memory 80M test - -If you started a container without kernel memory initialized: - - # docker run -ti --name test2 --memory 300M ubuntu bash - -Update kernel memory of running container `test2` will fail, you can only -stop the container and update kernel memory then. The next time you -restart it, the container uses the new value. - -Another configuration you can change with this command is restart policy, -new restart policy will take effect instantly after you run `docker update` -on a container. +kernel memory initialized. ## EXAMPLES The following sections illustrate ways to use this command. -### Update a container with cpu-shares=512 +### Update a container's 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: +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: ```bash $ docker update --cpu-shares 512 abebf7571666 @@ -82,9 +63,44 @@ 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 + +You can update a container's kernel memory limit using the `--kernel-memory` +option. 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. + +For example, if you started a container with this command: + +```bash +$ docker run -dit --name test --kernel-memory 50M ubuntu bash +``` + +You can update kernel memory while the container is running: + +```bash +$ docker update --kernel-memory 80M test +``` + +If you started a container *without* kernel memory initialized: + +```bash +$ 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. + + ### Update a container's restart policy +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: + ```bash $ docker update --restart=on-failure:3 abebf7571666 hopeful_morse ``` diff --git a/man/docker-update.1.md b/man/docker-update.1.md index 9d39d78b13..3dd6a4f989 100644 --- a/man/docker-update.1.md +++ b/man/docker-update.1.md @@ -22,37 +22,19 @@ CONTAINER [CONTAINER...] # DESCRIPTION -The `docker update` command dynamically updates container configuration. -you can Use this command to prevent containers from consuming too many +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` value, you can specify these +With the exception of the **--kernel-memory** option, you can specify these options on a running or a stopped container. You can only update -`--kernel-memory` on a stopped container or on a running container with -kernel memory initialized. For example, if you started a container with -command: - - # docker run -ti --name test --kernel-memory 50M ubuntu bash - -You can update kernel memory of this running container: - - # docker update --kernel-memory 80M test - -If you started a container without kernel memory initialized: - - # docker run -ti --name test2 --memory 300M ubuntu bash - -Update kernel memory of running container `test2` will fail, you can only -stop the container and update kernel memory then. The next time you -restart it, the container uses the new value. - -Another configuration you can change with this command is restart policy, -new restart policy will take effect instantly after you run `docker update` -on a container. +**--kernel-memory** on a stopped container or on a running container with +kernel memory initialized. # OPTIONS + **--blkio-weight**=0 Block IO weight (relative weight) accepts a weight value between 10 and 1000. @@ -77,9 +59,9 @@ on a container. **--kernel-memory**="" Kernel memory limit (format: `[]`, where unit = b, k, m or g) - Note that you can not update kernel memory to a running container if the container -is started without kernel memory initialized, in this case, it can only be updated -after it's stopped, and affect after it's started. + Note that you can not update kernel memory on a running container if the container + is started without kernel memory initialized, in this case, it can only be updated + after it's stopped. The new setting takes effect when the container is started. **-m**, **--memory**="" Memory limit (format: , where unit = b, k, m or g) @@ -97,7 +79,7 @@ after it's stopped, and affect after it's started. The following sections illustrate ways to use this command. -### Update a container with cpu-shares=512 +### Update a container's 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 @@ -115,9 +97,43 @@ 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 + +You can update a container's kernel memory limit using the **--kernel-memory** +option. 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. + +For example, if you started a container with this command: + +```bash +$ docker run -dit --name test --kernel-memory 50M ubuntu bash +``` + +You can update kernel memory while the container is running: + +```bash +$ docker update --kernel-memory 80M test +``` + +If you started a container *without* kernel memory initialized: + +```bash +$ 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. + ### Update a container's restart policy +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: + ```bash $ docker update --restart=on-failure:3 abebf7571666 hopeful_morse ```