Skip to content

Latest commit

 

History

History
204 lines (162 loc) · 6.67 KB

storage.md

File metadata and controls

204 lines (162 loc) · 6.67 KB
Raw

Storage

Limitador limits counters are stored in a backend storage. This is In contrast to the storage of the limits themselves, which are always stored in ephemeral memory. Limitador's operator supports several storage configurations:

  • In-Memory: ephemeral and cannot be shared
  • Redis: Persistent (depending on the redis storage configuration) and can be shared
  • Redis Cached: Persistent (depending on the redis storage configuration) and can be shared
  • Disk: Persistent (depending on the underlying disk persistence capabilities) and cannot be shared

In-Memory

Counters are held in Limitador (ephemeral)

In-Memory is the default option defined by the Limitador's Operator.

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage: null

For any of those, one should store the URL of the Redis service, inside a K8s opaque Secret.

apiVersion: v1
kind: Secret
metadata:
  name: redisconfig
stringData:
  URL: redis://127.0.0.1/a # Redis URL of its running instance
type: Opaque

Redis

Uses Redis to store counters.

Selected when spec.storage.redis is not null.

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    redis:
      configSecretRef: # The secret reference storing the URL for Redis
        name: redisconfig

The URL of the Redis service is provided inside a K8s opaque Secret. The secret is required to be in the same namespace as the Limitador CR.

apiVersion: v1
kind: Secret
metadata:
  name: redisconfig
stringData:
  URL: redis://127.0.0.1/a # Redis URL of its running instance
type: Opaque

Note: Limitador's Operator will only read the URL field of the secret.

Redis Cached

Uses Redis to store counters, with an in-memory cache.

Selected when spec.storage.redis-cached is not null.

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    redis-cached:
      configSecretRef: # The secret reference storing the URL for Redis
        name: redisconfig

The URL of the Redis service is provided inside a K8s opaque Secret. The secret is required to be in the same namespace as the Limitador CR.

apiVersion: v1
kind: Secret
metadata:
  name: redisconfig
stringData:
  URL: redis://127.0.0.1/a # Redis URL of its running instance
type: Opaque

Note: Limitador's Operator will only read the URL field of the secret.

Additionally, caching options can be specified in the spec.storage.redis-cached.options field.

Options

Option Description
batch-size Size of entries to flush in as single flush [default: 100]
flush-period Flushing period for counters in milliseconds [default: 1000]
max-cached Maximum amount of counters cached [default: 10000]
response-timeout Timeout for Redis commands in milliseconds [default: 350]

For example:

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    redis-cached:
      configSecretRef: # The secret reference storing the URL for Redis
        name: redisconfig
      options: # Every option is optional
        batch-size: 50
        max-cached: 5000

Disk

Counters are held on disk (persistent). Kubernetes Persistent Volumes will be used to store counters.

Selected when spec.storage.disk is not null.

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    disk: {}

Additionally, disk options can be specified in the spec.storage.disk.persistentVolumeClaim and spec.storage.disk.optimize fields.

Persistent Volume Claim Options

spec.storage.disk.persistentVolumeClaim field is an object with the following fields.

Field Description
storageClassName StorageClass of the storage offered by cluster administrators [default: default storage class of the cluster]
resources The minimum resources the volume should have. Resources will not take any effect when VolumeName is provided. This parameter is not updateable when the underlying PV is not resizable. [default: 1Gi]
volumeName The binding reference to the existing PersistentVolume backing this claim [default: null]

Example:

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    disk:
      persistentVolumeClaim:
        storageClassName: "customClass"
        resources:
          requests: 2Gi

Optimize

Defines the valid optimization option of the disk persistence type.

spec.storage.disk.optimize field is a string type with the following valid values:

Option Description
throughput Optimizes for higher throughput. Default
disk Optimizes for disk usage

Example:

apiVersion: limitador.kuadrant.io/v1alpha1
kind: Limitador
metadata:
  name: limitador-sample
spec:
  storage:
    disk:
      optimize: disk