# Tuning Component Settings Helm Charts are a set of Kubernetes manifests that reflect best practices for deploying an application or service. Helm is heavily influenced by [Homebrew](http://brew.sh/), including the [formula model](https://github.com/Homebrew/homebrew-core). A Helm Chart is to Helm as a Formula is to Homebrew. After you fetch the Workflow chart, you can customize the chart using `helmc edit` before using `helmc generate` and `helmc install` to complete the installation. To customize the respective component, edit `tpl/deis--rc.yaml` and modify the `env` section of the component to tune these settings. For example, to allow only administrators to register new accounts in the controller, edit `tpl/deis-controller-rc.yaml` and add the following under the `env` section: ``` env: - name: REGISTRATION_MODE value: "admin_only" ``` ## Setting Resource limits You can set resource limits to Workflow components by modifying the template file `tpl/generate_params.toml`. This file has a section for each Workflow component. To set a limit to any Workflow component just add `limits_cpu`, `limits_memory` in the section and set them to the appropriate values. Below is an example of how the builder section of `tpl/generate_params.toml` might look with CPU and memory limits set: ``` [builder] org = "deisci" pullPolicy = "Always" dockerTag = "canary" limits_cpu = "100m" limits_memory = "50Mi" ``` ## Customizing the Builder The following environment variables are tunable for the [Builder][] component: Setting | Description ------- | --------------------------------- DEBUG | Enable debug log output (default: false) ## Customizing the Controller The following environment variables are tunable for the [Controller][] component: Setting | Description ----------------------------------------------- | --------------------------------- REGISTRATION_MODE | set registration to "enabled", "disabled", or "admin_only" (default: "enabled") GUNICORN_WORKERS | number of [gunicorn][] workers spawned to process requests (default: CPU cores * 4 + 1) RESERVED_NAMES | a comma-separated list of names which applications cannot reserve for routing (default: "deis, deis-builder, deis-workflow-manager") SLUGRUNNER_IMAGE_NAME | the image used to run buildpack application slugs (default: "quay.io/deisci/slugrunner:canary") SLUG_BUILDER_IMAGE_PULL_POLICY | the kubernetes [image pull policy][pull-policy] for slugbuilder (default: "Always") DOCKER_BUILDER_IMAGE_PULL_POLICY | the kubernetes [image pull policy][pull-policy] for dockerbuilder (default: "Always") KUBERNETES_POD_TERMINATION_GRACE_PERIOD_SECONDS | how many seconds kubernetes waits for a pod to finish work after a SIGTERM before sending SIGKILL (default: 30) ### Global and per application settings Setting | Description ----------------------------------------------- | --------------------------------- DEIS_DEPLOY_BATCHES | the number of pods to bring up and take down sequentially during a scale (default: number of available nodes) DEIS_DEPLOY_TIMEOUT | deploy timeout in seconds per deploy batch (default: 120) KUBERNETES_DEPLOYMENTS_REVISION_HISTORY_LIMIT | how many [revisions][[kubernetes-deployment-revision]] Kubernetes keeps around of a given Deployment (default: all revisions) See the [Deploying Apps][] guide for more detailed information on those. ## Customizing the Database The following environment variables are tunable for the [Database][] component: Setting | Description ----------------- | --------------------------------- BACKUP_FREQUENCY | how often the database should perform a base backup (default: "12h") BACKUPS_TO_RETAIN | number of base backups the backing store should retain (default: 5) ## Customizing Fluentd The following environment variables are tunable for [Fluentd][logger]: Setting | Description ----------------- | --------------------------------- SYSLOG_HOST_1 | The hostname of a remote syslog endpoint for shipping logs SYSLOG_PORT_1 | The port of a remote syslog endpoint for shipping logs ## Customizing the Logger The following environment variables are tunable for the [Logger][] component: Setting | Description ----------------- | --------------------------------- STORAGE_ADAPTER | How to store logs that are sent to the logger (default: "memory") NUMBER_OF_LINES | How many lines to store in the ring buffer (default: 1000) ## Customizing the Monitor The monitor component uses [Telegraf](https://github.com/influxdata/telegraf) under the hood, and derives most of its configuration from it. Please see [telegraf configuration](https://github.com/influxdata/telegraf/blob/master/docs/CONFIGURATION.md) for more information on tuning the [Monitor][] component. ## Customizing the Registry The [Registry][] component can be tuned by following the [deis/distribution config doc](https://github.com/deis/distribution/blob/master/docs/configuration.md). ## Customizing the Router The majority of router settings are tunable through annotations, which allows the router to be re-configured with zero downtime post-installation. You can find the list of annotations to tune [here](https://github.com/deis/router#annotations). The following environment variables are tunable for the [Router][] component: Setting | Description ----------------- | --------------------------------- POD_NAMESPACE | The pod namespace the router resides in. This is set by the [Kubernetes downward API][downward-api]. ## Customizing Workflow Manager The following environment variables are tunable for [Workflow Manager][]: Setting | Description ---------------------------------- | --------------------------------- CHECK_VERSIONS | Enables the external version check at (default: "true") POLL_INTERVAL_SEC | The interval when Workflow Manager performs a version check, in seconds (default: 43200, or 12 hours) VERSIONS_API_URL | The versions API URL (default: "") DOCTOR_API_URL | The doctor API URL (default: "") API_VERSION | The version number Workflow Manager sends to the versions API (default: "v2") [Deploying Apps]: ../applications/deploying-apps.md [builder]: ../understanding-workflow/components.md#builder [controller]: ../understanding-workflow/components.md#controller [database]: ../understanding-workflow/components.md#database [Deployments]: http://kubernetes.io/docs/user-guide/deployments/ [downward-api]: http://kubernetes.io/docs/user-guide/downward-api/ [gunicorn]: http://gunicorn.org/ [kubernetes-deployment-revision]: http://kubernetes.io/docs/user-guide/deployments/#revision-history-limit [logger]: ../understanding-workflow/components.md#logger-fluentd-logger [monitor]: ../understanding-workflow/components.md#monitor [pull-policy]: http://kubernetes.io/docs/user-guide/images/ [registry]: ../understanding-workflow/components.md#registry [ReplicationControllers]: http://kubernetes.io/docs/user-guide/replication-controller/ [router]: ../understanding-workflow/components.md#router [workflow manager]: ../understanding-workflow/components.md#workflow-manager