% DOCKER(1) Docker User Manuals % Docker Community % JUNE 2014 # NAME docker-update - Update resource configs of one or more containers # SYNOPSIS **docker update** [**--blkio-weight**[=*[BLKIO-WEIGHT]*]] [**--cpu-shares**[=*0*]] [**--cpu-period**[=*0*]] [**--cpu-quota**[=*0*]] [**--cpuset-cpus**[=*CPUSET-CPUS*]] [**--cpuset-mems**[=*CPUSET-MEMS*]] [**--help**] [**--kernel-memory**[=*KERNEL-MEMORY*]] [**-m**|**--memory**[=*MEMORY*]] [**--memory-reservation**[=*MEMORY-RESERVATION*]] [**--memory-swap**[=*MEMORY-SWAP*]] CONTAINER [CONTAINER...] # DESCRIPTION The `docker update` command dynamically updates container resources. 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 options on a running or a stopped container. You can only update `--kernel-memory` on a stopped container. When you run `docker update` on stopped container, the next time you restart it, the container uses those values. # OPTIONS **--blkio-weight**=0 Block IO weight (relative weight) accepts a weight value between 10 and 1000. **--cpu-shares**=0 CPU shares (relative weight) **--cpu-period**=0 Limit the CPU CFS (Completely Fair Scheduler) period **--cpu-quota**=0 Limit the CPU CFS (Completely Fair Scheduler) quota **--cpuset-cpus**="" CPUs in which to allow execution (0-3, 0,1) **--cpuset-mems**="" Memory nodes(MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA systems. **--help** Print usage statement **--kernel-memory**="" Kernel memory limit (format: `<number>[<unit>]`, where unit = b, k, m or g) Note that you can not update kernel memory to a running container, it can only be updated to a stopped container, and affect after it's started. **-m**, **--memory**="" Memory limit (format: <number><optional unit>, where unit = b, k, m or g) **--memory-reservation**="" Memory soft limit (format: <number>[<unit>], where unit = b, k, m or g) **--memory-swap**="" Total memory limit (memory + swap) # EXAMPLES The following sections illustrate ways to use this command. ### Update a container with cpu-shares=512 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: ```bash $ docker update --cpu-shares 512 abebf7571666 ``` ### Update a container with cpu-shares and memory To update multiple resource configurations for multiple containers: ```bash $ docker update --cpu-shares 512 -m 300M abebf7571666 hopeful_morse ```