tmpfs İle init container desenine göre dosya paylaşımı

docker-compose.yaml

version: "3.8"

volumes:
  cache_vol:
    driver_opts:
      type: tmpfs
      device: tmpfs

services:
  init-container:
    image: busybox
    entrypoint: ["sh", "-c", "echo 'some data' > /config_1/shared-file"]
    volumes:
      - cache_vol:/config_1

  main-container:
    image: busybox
    entrypoint: ["sh", "-c", "cat /config_1/shared-file"]
    volumes:
      - cache_vol:/config_1
    depends_on:
      - init-container

Eğer entrypoint: ["sh", "-c", "echo 'some data' > /config_1/shared-file && echo 'done'"] satırıyla init-container başlatılırsa ekran çıktısı şöyle olur ve anlarız ki init bitmiş main başlamış ve bitmiş.

Kubernetes içinde koşabilen hali:

apiVersion: v1
kind: Pod
metadata:
  name: tmpfs-pod
spec:
  containers:
  - name: init-container
    image: busybox
    command: ["sh", "-c", "echo 'some data' > /config_1/shared-file && sleep 60"]
    volumeMounts:
    - name: cache-vol
      mountPath: /config_1

  - name: main-container
    image: busybox
    command: ["sh", "-c", "cat /config_1/shared-file"]
    volumeMounts:
    - name: cache-vol
      mountPath: /config_1

  volumes:
  - name: cache-vol
    emptyDir:
      medium: Memory  # emptyDir ile tmpfs kullanarak RAM üzerinde dosya saklanır