Architecture

The overall architecture of Crane is shown as below:

Craned

Craned is the core component which manage the lifecycle of CRDs and APIs. It’s deployed by a Deployment which consists of two container:

• Craned: Operators for management CRDs, WebApi for Dashboard, Predictors that provide query TimeSeries API.
• Dashboard: Web component that built from TDesign’s Starter, provide an easy-to-use UI for crane users.

Fadvisor

Fadvisor provides a collection of exporters which collect cloud resource pricing and billing data and ship to your monitoring system like Prometheus. Fadvisor support Multi-Cloud Pricing API by Cloud Provider.

Metric Adapter

Metric Adapter implements a Custom Metric Apiserver. Metric Adapter consume Crane CRDs and provide HPA Metrics by Custom/External Metric API.

Crane Agent

Crane Agent is a DaemonSet that runs in each node.

Repositories

Crane is composed of the following components:

• craned - main crane control plane.
• metric-adaptor - Metric server for driving the scaling.
• crane-agent - Ensure critical workloads SLO based on abnormally detection.
• gocrane/api - This repository defines component-level APIs for the Crane platform.
• gocrane/fadvisor - Financial advisor which collect resource prices from cloud API.
• gocrane/crane-scheduler - A Kubernetes scheduler which can schedule pod based on actual node load.
• kubectl-crane - Kubectl plugin for crane, including recommendation and cost estimate.