[eks/actions-runner-controller] Multiple bug fixes and enhancements

[Nuru]

what

New Features:

• Add support for scheduled overrides of Runner Autoscaler min and max replicas.
• Add option tmpfs_enabled to have runners use RAM-backed ephemeral storage (tmpfs, emptyDir.medium: Memory) instead of disk-backed storage.
• Add wait_for_docker_seconds to allow configuration of the time to wait for the Docker daemon to be ready before starting the runner.
• Enhance the ability to have the runner Pods add annotations to themselves once they start running a job.

Changes:

• Previously, syncPeriod, which sets the period in which the controller reconciles the desired runners count, was set to 120 seconds in resources/values.yaml. This setting has been removed, reverting to the default value of 1 minute. You can still set this value by setting the syncPeriod value in the values.yaml file or by setting syncPeriod in var.chart_values.
• Previously, RUNNER_GRACEFUL_STOP_TIMEOUT was hardcoded to 90 seconds. That has been reduced to 80 seconds.
• The inaccurately named webhook_startup_timeout has been replaced with max_duration. webhook_startup_timeout is still supported for backward compatibility, but is deprecated.

Bugfixes:

• Create and deploy the webhook secret when an existing secret is not supplied
• Restore proper order of operations in creating resources (broken in release 1.454.0 (PR [eks/actions-runner-controller] Add ability to dynamically annotate pods once they start a job #1055))
• If docker_storage is set and dockerdWithinRunnerContainer is true (which is hardcoded to be the case), properly mount the docker storage volume into the runner container rather than the (non-existent) docker sidecar container.

why

New Features:

• Enable having idle runners during work hours without having to pay for them during non-work hours.
• Enable packing more Runners onto an instance without being constrained by disk I/O.
• Allow for extended disk I/O waits when some Runner gets greedy.
• Intended to make idle Runners interruptible and running runners uninterruptible under Karpenter, but it does not work well enough for that. Still, we implemented the feature, so we might as well leave it in. Adds logging to help diagnose race conditions.

Changes:

• More responsive scaling
• Increases the chances the runner will successfully deregister itself
• The old name was extremely confusing, while the new name is much more reflective of its impact

Bugfixes:

• Restore intended operation

references

• Mega Issue: Node Disruption Lifecycle Taints kubernetes-sigs/karpenter#624
• fix: address disruption taint race condition kubernetes-sigs/karpenter#1180
• Taint nodes with a NoSchedule for Consolidation before Validation begins kubernetes-sigs/karpenter#651