simple-gang-scheduler

This repo is a simple gang scheduler implemented by scheduler framework in Kubernetes. This scheduler have a sample plugin, and implements queue sort and permit extension points. More information can be found in this blog.

Install

git clone git@github.com:FFFFFaraway/gang-scheduler.git
cd gang-scheduler
# create rbac
kubectl apply -f deploy/rbac.yaml
# create sceduler
kubectl apply -f deploy/deployment.yaml

You can change the scheduler name by edit the KubeSchedulerConfiguration in deploy/deployment.yaml file. Default name is gang-scheduler, and the default namespace is kube-system.

How to use

The scheduler use configmap to record podgroup information. For example:

apiVersion: v1
kind: ConfigMap
metadata:
  # PodGroup name
  name: pending-pg
  namespace: sw
data:
  # Minimum number of allocated pods belongs to this PodGroup
  minAvailable: "3"
  # Wait seconds in scheduler queue
  scheduleTimeoutSeconds: "5"

Pod use label to bind pod group. For example:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: pending-example
  # The namespace should be the same as the PodGroup it belongs to
  namespace: sw
spec:
  replicas: 2
  selector:
    matchLabels:
      app: busybox
  template:
    metadata:
      labels:
        app: busybox
        # This label bind this pod to the 'pending-pg' PodGroup
        pod-group.scheduling.bdap.com/podgroup-configmap: pending-pg
    spec:
      # use our sheduler
      schedulerName: gang-scheduler
      containers:
      - image: busybox
        name: busybox
        command: ["sleep", "infinity"]

More examples can be found in config directory.