Updated on 2025-08-11 GMT+08:00

Adding an Auto Scaling Policy for MRS Task Nodes

The auto scaling function of MRS enables the task nodes of a cluster to be automatically scaled to match cluster loads. If the data volume changes periodically, you can configure an auto scaling rule so that the number of task nodes can be automatically adjusted in a fixed period of time before the data volume changes.

  • Load-based Task node auto scaling: The number of Task nodes is adjusted based on the real-time cluster load metrics or cluster resource pool metrics. When the data volume changes, scaling is triggered but delayed.
  • Time-based Task node auto scaling: The number of Task nodes is adjusted based on the time ranges. If the data volume changes periodically, you can specify a resource plan to scale in or out the cluster before the data volume changes so as to avoid scaling delay.

You can configure load-based, time-based, or both of Task node auto scaling. It is recommended to use both of the node auto scaling in case of the unexpected data peaks.

For more information about auto scaling policies, see Automatic Scaling of Task Nodes in an MRS Cluster.

Video Tutorial

This tutorial demonstrates how to configure AS when purchasing a cluster and how to add an AS policy to an existing cluster.

The UI may vary depending on the version. This tutorial is for reference only.

Configuring Auto Scaling During Cluster Creation

When you create a cluster, you can configure the auto scaling function in advanced configuration parameters. Auto scaling policies can be configured during cluster creation only for analysis, streaming, and hybrid clusters.

  1. Log in to the MRS console.
  2. When you buy a cluster containing task nodes, configure the cluster software and hardware information by referring to Buying a Custom MRS Cluster. Then, on the Set Advanced Options page, enable Analysis Task and configure or modify auto scaling rules and resource plans.

    Figure 1 Configuring auto scaling rules when creating a cluster

    Note that the auto scaling adjusts the number of nodes as well as costs. Exercise caution when configuring auto scaling.

    You can configure auto scaling as follows:

Adding an Auto Scaling Policy for a Cluster

After a cluster is created, you can configure rules for the task node group in a cluster by node group or resource pool.

The node group policy and resource pool policy are mutually exclusive. You can configure either of them as needed.

You can specify the auto scaling policy by resource pool in MRS 3.1.5 or later.

Item

By Node Group

By Resource Pool

Auto scaling object

All nodes in the task node group

Task nodes in the resource pool specified by an auto scaling policy

Resource pool ownership of added nodes

Default resource pool

Resource pool specified by the auto scaling policy

Scale-in object

Random scale-in of nodes in the task node group

Random scale-in of nodes in a resource pool specified by an auto scaling policy

Notes and Constraints

  • The auto scaling policy can be enabled for only one node group.
  • Only the following versions support auto scaling by resource pool:
    • Common MRS: MRS 3.1.5 or later
    • LTS MRS: MRS 3.3.0-LTS or later

Prerequisites

Procedure

  1. Log in to the MRS console.
  2. On the Active Clusters page, click the name of the target cluster. The cluster details page is displayed.
  3. On the page that is displayed, click the Auto Scaling tab.

    You can configure policies by resource pool or node group as needed.

    Figure 4 Selecting an auto scaling dimension

  4. Click Create Auto Scaling Policy to create an auto scaling policy.

    Figure 5 Adding an auto scaling policy (by node group)

    You can configure auto scaling as follows:

Helpful Links