Help Center/ MapReduce Service/ User Guide/ MRS Cluster O&M/ MRS Cluster Alarm Handling Reference/ ALM-14038 Router Heap Memory Usage Exceeds the Threshold
Updated on 2024-11-13 GMT+08:00

ALM-14038 Router Heap Memory Usage Exceeds the Threshold

Alarm Description

The system checks the size of the used HDFS Router heap memory and the maximum size of the heap memory that can be allocated every 30 seconds, calculates the ratio of the used heap memory to the maximum size of the heap memory that can be allocated to obtain the heap memory usage, and compares the actual heap memory usage of the HDFS Router with the threshold. The HDFS Router Heap Memory usage has a default threshold. This alarm is generated when the HDFS Router Heap Memory usage exceeds the threshold.

You can change the threshold in O&M > Alarm > Thresholds > Name of the desired cluster > HDFS.

The alarm is cleared when the heap memory usage is less than or equal to the threshold.

This alarm applies only to MRS 3.5.0 or later.

Alarm Attributes

Alarm ID

Alarm Severity

Auto Cleared

14038

Critical (default threshold: 95%)

Major (default threshold: 90%)

Yes

Alarm Parameters

Type

Parameter

Description

Location Information

Source

Specifies the cluster for which the alarm is generated.

ServiceName

Specifies the service for which the alarm is generated.

RoleName

Specifies the role for which the alarm is generated.

HostName

Specifies the host for which the alarm is generated.

Additional Information

Trigger Condition

Specifies the alarm triggering condition.

Impact on the System

The HDFS Router Heap Memory usage is too high, which affects the data read/write performance of the HDFS.

Possible Causes

The HDFS Router Heap Memory is insufficient.

Handling Procedure

  1. On FusionInsight Manager, choose Cluster > Services > Ranger > Instance > PolicySync. Click Instance Configuration and then All Configurations, and choose PolicySync > System.
  2. On the FusionInsight Manager portal, choose Cluster > Services > HDFS > Configurations > All Configurations. In Search, enter GC_OPTS to check the GC_OPTS memory parameter of HDFS->Router.
  3. Increase the values of -Xms and -Xmx in the GC_OPTS parameter based on the site requirements and save the configuration.

    If this alarm is generated, the heap memory configured for Router cannot meet the requirements of the current process. You are advised to change the values of -Xms and -Xmx in the GC_OPTS parameter to twice the size of the used heap memory or change the values based on the site requirements.

  4. Restart the affected services or instances and check whether the alarm is cleared.

    • If yes, no further action is required.
    • If no, go to 5.

Collect fault information.

  1. On FusionInsight Manager, choose O&M. In the navigation pane on the left, choose Log > Download.
  2. Expand the Service drop-down list, and select HDFS for the target cluster.
  3. Click the edit icon in the upper right corner, and set Start Date and End Date for log collection to 10 minutes ahead of and after the alarm generation time, respectively. Then, click Download.
  4. Contact O&M engineers and provide the collected logs.

Alarm Clearance

This alarm is automatically cleared after the fault is rectified.

Related Information

None.