This should reduce potential CPU throttling and OOMKills on containers.
Possible drawbacks
This creates an empty env key for those not setting resource values. This is only a little ugly, but should not be harmful. Alternatively, we could add some conditional wrapper around the whole env block to only make it appear if a value is set, but that will be more complicated if additional env would be added in the future.
Applicable issues
N/A
Additional information
The resourceFieldRef is a very specific Kubernetes directive that is created specifically for passing resource-related values, which rounds up the CPU value to the nearest whole number (e.g. 250m to 1) and passes the memory as a numeric value; so 64Mi would result in the environment variable being set to 67108864. This by design makes it completely compatible with Go's API.
Description of the change
Set
GOMAXPROCSandGOMEMLIMITenvironment variables based on container resources.Inspired by https://github.com/traefik/traefik-helm-chart/pull/1029.
Benefits
This should reduce potential CPU throttling and OOMKills on containers.
Possible drawbacks
This creates an empty
envkey for those not setting resource values. This is only a little ugly, but should not be harmful. Alternatively, we could add some conditional wrapper around the wholeenvblock to only make it appear if a value is set, but that will be more complicated if additional env would be added in the future.Applicable issues
N/A
Additional information
The
resourceFieldRefis a very specific Kubernetes directive that is created specifically for passing resource-related values, which rounds up the CPU value to the nearest whole number (e.g. 250m to 1) and passes the memory as a numeric value; so64Miwould result in the environment variable being set to67108864. This by design makes it completely compatible with Go's API.An example is documented within Kubernetes documentation itself: https://kubernetes.io/docs/tasks/inject-data-application/environment-variable-expose-pod-information/#use-container-fields-as-values-for-environment-variables.