Resource Management

New

Introduced in 0.15.0

resource:limit [--process-type <process-type>] [RESOURCE_OPTS...] <app>    # Limit resources for a given app/process-type combination
resource:limit-clear [--process-type <process-type>] <app>                 # Limit resources for a given app/process-type combination
resource:report [<app>] [<flag>]                                           # Displays a resource report for one or more apps
resource:reserve [--process-type <process-type>] [RESOURCE_OPTS...] <app>  # Reserve resources for a given app/process-type combination
resource:reserve-clear [--process-type <process-type>] <app>               # Reserve resources for a given app/process-type combination

The resource plugin is meant to allow users to limit or reserve resources for a given app/process-type combination.

Usage

By default, Dokku allows unlimited resource access to apps deployed on a server. In some cases, it may be desirable to limit this on a per-app or per-process-type basis. The resource plugin allows management of both resource "limits" and resource "reservations", where each resource request type has specific meaning to the scheduler in use for a given app.

Warning

The meaning of a values and it's units are specific to the scheduler in use for a given app. If a value is incorrect for a scheduler, this may result in containers failing to start correctly. If a scheduler does not support a given resource type combination, it will be ignored. All resource commands require an app rebuild or deploy in order to take effect.

Valid resource options include:

• --cpu
• --memory
• --memory-swap
• --network
• --network-ingress
• --network-egress
• --nvidia-gpu

See the Supported Resource Management Properties section of the docker local scheduler documentation for more information on how each resource limit maps to Docker.

Resource limits and reservations are applied only during the run and deploy phases of an application, and will not impact the build phase of an application.

Resource Limits

When specified and supported, a resource limit will ensure that your app does not go over the specified value. If this occurs, the underlying scheduler may either cap resource utilization, or it may decide to terminate and reschedule your process.

Resource limits may be set via the resource:limit command:

ShellOutput

dokku resource:limit --memory 100 node-js-app

=====> Setting resource limits for node-js-app
       memory: 100

Multiple resources can be limited in a single call:

ShellOutput

dokku resource:limit --cpu 100 --memory 100 node-js-app

=====> Setting resource limits for node-js-app
       cpu: 100
       memory: 100

Resources can also be limited on a per-process type basis. If specified, this will override any generic limits set for the app.

ShellOutput

dokku resource:limit --cpu 100 --memory 100 --process-type worker node-js-app

=====> Setting resource limits for node-js-app (worker)
       cpu: 100
       memory: 100

Displaying Resource Limits

Running the resource:limit command without any flags will display the currently configured default app limits.

ShellOutput

dokku resource:limit node-js-app

=====> resource limits node-js-app information [defaults]
       cpu:
       memory:
       memory-swap: 100
       network: 100
       network-ingress:
       network-egress:
       nvidia-gpu:

This may also be combined with the --process-type flag to see app limits on a process-type level. Note that the displayed values are not merged with the defaults.

ShellOutput

dokku resource:limit --process-type web node-js-app

=====> resource limits node-js-app information (web)
       cpu: 100
       memory: 100
       memory-swap:
       network:
       network-ingress:
       network-egress:
       nvidia-gpu:

Clearing Resource Limits

In cases where the values are incorrect - or there is no desire to limit resources - resource limits may be cleared using the resource:limit-clear command.

ShellOutput

dokku resource:limit-clear node-js-app

-----> Clearing resource limit for node-js-app

Defaults can also be cleared by leaving the app unspecified.

ShellOutput

dokku resource:limit-clear

-----> Clearing default resource limits

Resource Reservations

When specified and supported, a resource reservation will ensure that your server has at least the specified resources before placing a given app's process. If there a resource exhaustion, future rebuilds and deploys may fail.

Resource reservations may be set via the resource:reserve command:

ShellOutput

dokku resource:reserve --memory 100 node-js-app

=====> Setting resource reservation for node-js-app
       memory: 100

Multiple resources can be limited in a single call:

ShellOutput

dokku resource:reserve --cpu 100 --memory 100 node-js-app

=====> Setting resource reservation for node-js-app
       cpu: 100
       memory: 100

Resources can also be limited on a per-process type basis. If specified, this will override any generic limits set for the app.

ShellOutput

dokku resource:reserve --cpu 100 --memory 100 --process-type worker node-js-app

=====> Setting resource reservation for node-js-app (worker)
       cpu: 100
       memory: 100

Displaying Resource Reservations

Running the resource:reserve command without any flags will display the currently configured default app reservations.

ShellOutput

dokku resource:reserve node-js-app

=====> resource reservation node-js-app information [defaults]
       cpu: 100
       memory: 100
       memory-swap:
       network:
       network-ingress:
       network-egress:
       nvidia-gpu:

This may also be combined with the --process-type flag to see app reservations on a process-type level. Note that the displayed values are not merged with the defaults.

ShellOutput

dokku resource:reserve --process-type web node-js-app

=====> resource reservation node-js-app information (web)
       cpu: 100
       memory: 100
       memory-swap:
       network:
       network-ingress:
       network-egress:
       nvidia-gpu:

Clearing Resource Reservations

In cases where the values are incorrect - or there is no desire to reserve resources - resource reservations may be cleared using the resource:reserve-clear command.

ShellOutput

dokku resource:reserve-clear node-js-app

-----> Clearing resource reservation for node-js-app

Defaults can also be cleared by leaving the app unspecified.

ShellOutput

dokku resource:reserve-clear

-----> Clearing default resource reservation

Displaying resource reports for an app

You can get a report about the app's resource status using the resource:report command:

ShellOutput

dokku resource:report

=====> node-js-app resource information
       web limit cpu:
       web limit memory: 1024
       web limit memory swap: 0
       web limit network: 10
       web limit network ingress:
       web limit network egress:
       web limit nvidia gpu:
       web reservation cpu:
       web reservation memory: 512
       web reservation memory swap:
       web reservation network: 8
       web reservation network ingress:
       web reservation network egress:
       web reservation nvidia gpu:
=====> python-sample resource information
       web limit cpu:
       web limit memory:
       web limit memory swap:
       web limit network:
       web limit network ingress:
       web limit network egress:
       web limit nvidia gpu:
       web reservation cpu:
       web reservation memory:
       web reservation memory swap:
       web reservation network:
       web reservation network ingress:
       web reservation network egress:
       web reservation nvidia gpu:
=====> ruby-sample resource information
       web limit cpu:
       web limit memory:
       web limit memory swap:
       web limit network:
       web limit network ingress:
       web limit network egress:
       web limit nvidia gpu:
       web reservation cpu:
       web reservation memory:
       web reservation memory swap:
       web reservation network:
       web reservation network ingress:
       web reservation network egress:
       web reservation nvidia gpu:

You can run the command for a specific app also.

ShellOutput

dokku resource:report node-js-app

=====> node-js-app resource information
       web limit cpu:
       web limit memory: 1024
       web limit memory swap: 0
       web limit network: 10
       web limit network ingress:
       web limit network egress:
       web limit nvidia gpu:
       web reservation cpu:
       web reservation memory: 512
       web reservation memory swap:
       web reservation network: 8
       web reservation network ingress:
       web reservation network egress:
       web reservation nvidia gpu:

You can pass flags which will output only the value of the specific information you want. For example:

ShellOutput

# Note the periods in the flag name
dokku resource:report node-js-app --resource-web.limit.memory

1024