This topic describes how to view the node changes caused by auto scaling in your E-MapReduce (EMR) cluster and the status of auto scaling activities.
Prerequisites
A DataLake cluster in the new data lake scenario, a Dataflow cluster, an online analytical processing (OLAP) cluster, a DataServing cluster, or a custom cluster is created. For more information, see Create a cluster.
An auto scaling rule is configured for the cluster. For more information, see Add auto scaling rules.
Procedure
Go to the Auto Scaling tab.
Log on to the EMR console. In the left-side navigation pane, click EMR on ECS.
In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
On the EMR on ECS page, find the desired cluster and click the name of the cluster in the Cluster ID/Name column.
On the page that appears, click the Auto Scaling tab.
Click the Auto Scaling Activity Analysis tab.
On this page, you can view the following information:
Data charts of auto scaling activities
Chart name
Description
Cluster Overview
Displays the hourly changes in the number of nodes and the number of cores within the specified time period.
Instance Distribution of Payment
Displays the hourly changes in the number of pay-as-you-go instances, the number of preemptible instances, and the number of cores within the specified time period.
Cluster Core Hour
Displays the hourly changes in the number of the cores of pay-as-you-go and preemptible instances within the specified time period.
Scaling Overview
Displays the hourly changes in the number of nodes that are created and released by auto scaling within the specified time period.
Scale Success/Failed Activities Count
Displays the hourly changes in the number of successful and failed auto scaling activities within the specified time period.
Distribution of Reasons for Scale Failed Activities
Displays the proportion of causes of auto scaling failures within the specified time period.
Status of auto scaling activities
State
Description
Running
The auto scaling activity is in progress.
Successful
All nodes specified in the auto scaling rule are added to or removed from the cluster during the auto scaling activity.
Failed
No nodes specified in the auto scaling rule are added to or removed from the cluster during the auto scaling activity.
Request Denied
The auto scaling activity is rejected. If the number of nodes in the auto scaling group is greater than the upper limit or less than the lower limit, the auto scaling activity cannot be performed. If the previous auto scaling activity is not complete, the auto scaling rule cannot be triggered.