Guides
Flightcontrol
Scheduler

Configuring Scheduler Services with flightcontrol.json

In addition to the Service Configuration attributes that are common to all services, the following attributes are specific to worker services.

If you are using pre-built docker images with the Image Registry feature, or building using a Custom Docker image, make sure not to add an ENTRYPOINT with a long running command. If you want to purpose the same image for other services like a web server, make sure to use CMD for your web server start command.

Scheduler Service Attributes

The type for all web server services is scheduler, and should be specified like the following:

type: 'scheduler'

In addition, there are other attributes that are specific to scheduler services:

Target

target.type: 'fargate' | 'ecs-ec2'

  • Example: "target": {"type": "fargate"}
  • Defaults to fargate
  • Fargate is a fully managed, pay-as-you-go compute engine that lets you focus on building apps without managing servers. It's the easiest to use. The tradeoffs are that it does not support GPUs or custom instance types, and can be up to 1.5 times more expensive than ECS+EC2, depending on how well you optimize the EC2 compute.
  • ECS+EC2 is AWS's version of Kubernetes. It gives you advance control over the cluster instance type and supports GPUs. It enables leveraging Reserved Instances for 50% or more savings. The tradeoffs are that 1) you have to manage the instance size to ensure there is enough CPU and memory for your app, 2) autoscaling is up to 2x slower if you don't have empty EC2 instances on standby, and 3) you have to manage the config options optimize compute across instances to minimize wasted resources.

If target is fargate: no other fields

If target is ecs-ec2:

target.clusterInstanceSize: string

target.clusterMinInstances: number

  • Example: "clusterMinInstances": 1
  • Minimum 1
  • Fastest deploys are possible when this is at least 2x the number of app instances running
  • Faster autoscaling is enabled when this is higher than minimum app instances so that machines are already running

target.clusterMaxInstances: number

  • Example: "clusterMaxInstances": 5
  • Minimum same as clusterMinInstances
  • Recommended to be at least 2x your max app instances config for seamless rolling deploys

Scheduler CPU

cpu: number

  • Example: "cpu": 0.25
  • This is the AWS vCPU unit for each service instance. It does not correspond to number of cores. It’s an abstract unit of CPU power defined by Amazon
  • This value will be used as the default CPU for the job when the CPU is not set in the job
  • Supported values:

Scheduler Memory

memory: number

  • Example: "memory": 1
  • In gigabytes
  • This value will be used as the default memory for the job when the memory is not set in the job
  • Supported values:
    • If target fargate:
      • With cpu: 0.25 - 0.5, 1, 2 With cpu: 0.5 - 1...4 (intervals of 1)
      • With cpu: 1 - 2...8 (intervals of 1)
      • With cpu: 2 - 4...16 (intervals of 1)
      • With cpu: 4 - 8...30 (intervals of 1)
      • With cpu: 8 - 16...60 (intervals of 4)
      • With cpu: 16 - 32...120 (intervals of 8)
      • For more details on Fargate configuration, see AWS’s Fargate pricing page (opens in a new tab)
    • If target ecs-ec2: range: 0.125 to 0.25 less than the memory of clusterInstanceSize. (0.25 GB is reserved for the ECS agent)

Scheduler GPU

gpu: integer

  • Example: "gpu": 1
  • This is how many GPUs to expose to your container
  • This value will be used as the default GPU for the job when the GPU is not set in the job
  • Supported values:
    • If target fargate: 0 or undefined
    • If target ecs-ec2: Range 0 to the GPU of clusterInstanceSize (requires a GPU compatible instance size)

Jobs

jobs: Record<string, JobConfig>

  • Example: "jobs": {"process-reports": {/* config here */}}
  • An object, where the key is the givenId that will be used to display the job in the dashboard
  • See the next section for supported fields in the job object

JobConfig

startCommand: string | string[]

  • Example: "startCommand": "php artisan run:billing-cycle"
  • Supported values:
    • Nixpacks: string
    • Custom Dockerfile: string or string[]
  • The command will be executed from the context of the application directory
  • The command should gracefully exit upon success with exit code 0, otherwise the execution will be marked as failed

schedule: string

  • Example: "schedule": "* * 1 * *"
  • Supported values:
  • Schedule is used to define the interval of running this job or to mark the job as manual and runs on demand

timezone: string

  • Example: "timezone": "America/New_York"
  • Optional with default: "UTC"
  • Supports any of the available timezones here (opens in a new tab).

cpu: number | undefined

  • Example: "cpu": 0.25
  • Optional, defaults to the CPU set in the base scheduler config
  • This is the AWS vCPU unit for each service instance. It does not correspond to number of cores. It’s an abstract unit of CPU power defined by Amazon
  • Supported values:

memory: number | undefined

  • Example: "memory": 1
  • Optional, defaults to the memory set in the base scheduler config
  • In gigabytes
  • Supported values:
    • If target fargate:
      • With cpu: 0.25 - 0.5, 1, 2 With cpu: 0.5 - 1...4 (intervals of 1)
      • With cpu: 1 - 2...8 (intervals of 1)
      • With cpu: 2 - 4...16 (intervals of 1)
      • With cpu: 4 - 8...30 (intervals of 1)
      • With cpu: 8 - 16...60 (intervals of 4)
      • With cpu: 16 - 32...120 (intervals of 8)
      • For more details on Fargate configuration, see AWS’s Fargate pricing page (opens in a new tab)
    • If target ecs-ec2: range: 0.125 to 0.25 less than the memory of clusterInstanceSize. (0.25 GB is reserved for the ECS agent)

gpu: integer | undefined

  • Example: "gpu": 1
  • Optional, defaults to the GPU set in the base scheduler config
  • This is how many GPUs to expose to your container
  • Supported values:
    • If target fargate: 0 or undefined
    • If target ecs-ec2: Range 0 to the GPU of clusterInstanceSize (requires a GPU compatible instance size)

timeout: int

  • Example: "timeout": 10
  • Timeout is in minutes
  • Optional with default: 480
  • Supported values: 1...1440

Container Insights

containerInsights: boolean

From Service

fromService: string

  • If using buildType: fromService, this is the ID of the service that you wish to use the image for.

Container Image

containerImage: object

  • containerImage defines the parameters needed when using buildType: fromRepository

    registryId: string

    • Example: "registryId": "ecr-9l03731"
    • Registry ID, you can find this on the Registries page in our dashboard

    repository: string

    • Example: "repository": "node:18-slim"
    • This is the URI of the image repository you wish to access

    tag?: string

    • Example: "tag": "latest"
    • Optional
    • This is the tag of the image from the repository that you would like to use

Docker Labels

dockerLabels: Record<string, string>

  • Example: "dockerLabels": {"com.example.vendor": "ACME"}
  • Optional
  • Will apply the set labels to the container

Version History Count

versionHistoryCount: number

  • Example: "versionHistoryCount": 15
  • Optional with default: 10
  • How many previous container images to keep in ECR. This determines how far back you can rollback. ECR storage is $0.10 per GB / month, so this configuration is balance between cost and rollback history.

Runtime-only Environment variables

includeEnvVariablesInBuild: boolean

  • Example: "includeEnvVariablesInBuild": false
  • Optional with default: true
  • Enables runtime-only environment variables - see the Configuring Environment Variables page for more details.

Integrations

integrations: object

Under the integrations key, you can configure integrations with third-party services. At this time, the only supported integration is with Sentry (opens in a new tab).

Upload Sentry Source Maps

uploadSentrySourceMap: boolean

  • Example: "integrations": { "uploadSentrySourceMap": true }
  • Optional with default: false
  • Enables uploading source maps to Sentry. This is useful for debugging errors in production. For more, see our Sentry guide.

Sidecars

sidecars: array

  • Example:
 "sidecars": [
        {
          "name": "open-telemetry-collector",
          "image": "otel/opentelemetry-collector-contrib:0.83.0",
          "cpuAllotment": 0.1,
          "memoryAllotment": 0.25,
          "enableNetworking": true,
          "ports": [4318]
        }
      ]
  • Optional with default: []
  • Enables sidecars for your service. For more, see our sidecars guide.

For each individual sidecar, you can configure the following attributes:

  • name - The name of the sidecar container.
  • image - The URL to the image for the sidecar container.
  • cpuAllotment - The absolute amount of CPU to allocate to the sidecar container. In vCPU units. For example, 0.25 would be 1/4 of a vCPU.
  • memoryAllotment - The absolute amount of memory to allocate to the sidecar container. In GB units. For example, 0.5 would be 1/2 of a GB.
  • enableNetworking - Whether to enable networking for the sidecar container. Defaults to true.
  • ports - An array of ports to expose from the sidecar container. Defaults to [].
  • envVariables - An object of environment variables to set in the sidecar container. Defaults to {}. You can use the same rules for environment variables as you would for your main container.
  • dockerLabels - An object of Docker labels to set in the sidecar container. Defaults to {}.

Extra options for Nixpacks

basePath?: string

  • Allows you to specify in which folder the commands should run
  • Example: "basePath": "./apps"
  • Optional, defaults to "./"

installCommand: string

  • Example: "installCommand": "./install.sh"
  • Optional, intelligent default based on your language and framework detected at the basePath
  • What we use to install dependencies for your build

buildCommand: string

  • Example: "buildCommand": "blitz build"
  • Optional, intelligent default based on your language and framework detected at the basePath
  • What we use to build your app

preDeployCommand: Array<string>

  • Example: "preDeployCommand": ["bundle", "exec", "rails", "db:prepare"],
  • Optional
  • A command that runs after successful build and before starting the deploy (more information).
  • If configured, a dedicated container is started to run the command and shuts down on completion.
  • The command must be split into array parts because this is used to override the Docker CMD, and if passed as a single string runc counts it as a single command instead of a command + arguments.
  • Note: using this for database migrations will add 2-3 minutes to your deploy time because of the time it takes this temporary container to boot and run.

postDeployCommand: Array<string>

  • Example: "postDeployCommand": ["node", "script.js"]
  • Optional
  • A command that runs after successful deploy (more information).
  • If configured, a dedicated container is started to run the command and shuts down on completion.
  • The command must be split into array parts because this is used to override the Docker CMD, and if passed as a single string runc counts it as a single command instead of a command + arguments.

postBuild: string

  • Example: "postBuild": "./postbuild.sh"
  • Optional, Empty by Default
  • Used as a build hook to run any operation after your build is complete

Extra options for custom Dockerfile only

dockerfilePath: string

  • Example: "dockerfilePath": "packages/web/Dockerfile"
  • Relative path to the Dockerfile from your repo root
  • It’s recommended to use ENTRYPOINT instead of CMD for your start command
  • You can authenticate with Docker Hub by adding your Docker Hub credentials as DOCKER_USERNAME and DOCKER_PASSWORD environment variables. If these env variables are present, we’ll run docker login with them. This will prevent Docker Hub rate limit issues.

dockerContext: string

  • Example: "dockerContext": "packages/web"
  • Optional with default: "." (repo root)
  • Relative path to the docker context from the repo root
  • It’s recommended to use ENTRYPOINT instead of CMD for your start command