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SingleStoreAutoscaler

What is SingleStoreAutoscaler

SingleStoreAutoscaler is a Kubernetes Custom Resource Definitions (CRD). It provides a declarative configuration for autoscaling SingleStore compute resources and storage of database components in a Kubernetes native way.

SingleStoreAutoscaler CRD Specifications

Like any official Kubernetes resource, a SingleStoreAutoscaler has TypeMeta, ObjectMeta, Spec and Status sections.

Here, some sample SingleStoreAutoscaler CROs for autoscaling different components of database is given below:

Sample SingleStoreAutoscaler for cluster database:

apiVersion: autoscaling.kubedb.com/v1alpha1
kind: SinglestoreAutoscaler
metadata:
  name: sdb-as-cluster
  namespace: demo
spec:
  databaseRef:
    name: sdb-sample
  storage:
    leaf:
      trigger: "On"
      usageThreshold: 30
      scalingThreshold: 50
      expansionMode: "Offline"
      upperBound: "100Gi"
    aggregator:
      trigger: "On"
      usageThreshold: 40
      scalingThreshold: 50
      expansionMode: "Offline"
      upperBound: "100Gi"
  compute:
    aggregator:
      trigger: "On"
      podLifeTimeThreshold: 5m
      minAllowed:
        cpu: 900m
        memory: 3000Mi
      maxAllowed:
        cpu: 2000m
        memory: 6Gi
      controlledResources: ["cpu", "memory"]
      resourceDiffPercentage: 10
    leaf:
      trigger: "On"
      podLifeTimeThreshold: 5m
      minAllowed:
        cpu: 900m
        memory: 3000Mi
      maxAllowed:
        cpu: 2000m
        memory: 6Gi
      controlledResources: ["cpu", "memory"]
      resourceDiffPercentage: 10

Sample SingleStoreAutoscaler for standalone database:

apiVersion: autoscaling.kubedb.com/v1alpha1
kind: SinglestoreAutoscaler
metadata:
  name: sdb-as-standalone
  namespace: demo
spec:
  databaseRef:
    name: sdb-standalone
  storage:
    node:
      trigger: "On"
      usageThreshold: 40
      scalingThreshold: 50
      expansionMode: "Offline"
      upperBound: "100Gi"
  compute:
    node:
      trigger: "On"
      podLifeTimeThreshold: 5m
      minAllowed:
        cpu: 900m
        memory: 3000Mi
      maxAllowed:
        cpu: 2000m
        memory: 6Gi
      controlledResources: ["cpu", "memory"]
      resourceDiffPercentage: 10

Here, we are going to describe the various sections of a SingleStoreAutoscaler crd.

A SingleStoreAutoscaler object has the following fields in the spec section.

spec.databaseRef

spec.databaseRef is a required field that point to the SingleStore object for which the autoscaling will be performed. This field consists of the following sub-field:

• spec.databaseRef.name : specifies the name of the SingleStore object.

spec.opsRequestOptions

These are the options to pass in the internally created opsRequest CRO. opsRequestOptions has three fields. They have been described in details here.

spec.compute

spec.compute specifies the autoscaling configuration for the compute resources i.e. cpu and memory of the database components. This field consists of the following sub-field:

• spec.compute.standalone indicates the desired compute autoscaling configuration for a standalone SingleStore database.
• spec.compute.aggregator indicates the desired compute autoscaling configuration for aggregator node of cluster mode.
• spec.compute.leaf indicates the desired compute autoscaling configuration for the leaf node of cluster mode.

All of them has the following sub-fields:

• trigger indicates if compute autoscaling is enabled for this component of the database. If “On” then compute autoscaling is enabled. If “Off” then compute autoscaling is disabled.
• minAllowed specifies the minimal amount of resources that will be recommended, default is no minimum.
• maxAllowed specifies the maximum amount of resources that will be recommended, default is no maximum.
• controlledResources specifies which type of compute resources (cpu and memory) are allowed for autoscaling. Allowed values are “cpu” and “memory”.
• containerControlledValues specifies which resource values should be controlled. Allowed values are “RequestsAndLimits” and “RequestsOnly”.
• resourceDiffPercentage specifies the minimum resource difference between recommended value and the current value in percentage. If the difference percentage is greater than this value than autoscaling will be triggered.
• podLifeTimeThreshold specifies the minimum pod lifetime of at least one of the pods before triggering autoscaling.

spec.storage

spec.compute specifies the autoscaling configuration for the storage resources of the database components. This field consists of the following sub-field:

• spec.compute.standalone indicates the desired storage autoscaling configuration for a standalone SingleStore database.
• spec.compute.leaf indicates the desired storage autoscaling configuration for leaf node of cluster mode.
• spec.compute.aggregator indicates the desired storage autoscaling configuration for aggregator node of cluster mode.

All of them has the following sub-fields:

• trigger indicates if storage autoscaling is enabled for this component of the database. If “On” then storage autoscaling is enabled. If “Off” then storage autoscaling is disabled.
• usageThreshold indicates usage percentage threshold, if the current storage usage exceeds then storage autoscaling will be triggered.
• scalingThreshold indicates the percentage of the current storage that will be scaled.
• expansionMode indicates the volume expansion mode.