• MapReduce Service

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  6. ALM-18009 Heap Memory Usage of MapReduce JobHistoryServer Exceeds the Threshold

ALM-18009 Heap Memory Usage of MapReduce JobHistoryServer Exceeds the Threshold

Description

The system checks the heap memory usage of MapReduce JobHistoryServer every 30 seconds and compares the actual usage with the threshold. The alarm is generated when the heap memory usage of MapReduce JobHistoryServer exceeds the threshold (80% of the maximum memory by default).

To change the threshold, choose System > Threshold Configuration > Service > MapReduce. This alarm is cleared when the heap memory usage of MapReduce JobHistoryServer is less than or equal to the threshold.

Attribute

Alarm ID

Alarm Severity

Automatically Cleared

18009

Major

Yes

Parameters

Parameter

Description

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.

Trigger Condition

Generates an alarm when the actual indicator value exceeds the specified threshold.

Impact on the System

Overhigh heap memory usage of the MapReduce JobHistoryServer deteriorates performance of MapReduce log archiving or even causes OOM, which results in unavailable MapReduce service.

Possible Causes

The heap memory of the MapReduce JobHistoryServer instance is overused or inappropriately allocated.

Procedure

Check the memory usage.

  1. On MRS Manager, click Alarm and select the alarm whose Alarm ID is 18009. Then check the IP address and role name of the instance in Location.
  2. On MRS Manager, choose Service > MapReduce > Instance > JobHistoryServer > Customize > Percentage of Used Heap Memory of the JobHistoryServer.
  3. JobHistoryServer indicates the corresponding HostName of the instance for which the alarm is generated. Check the heap memory usage.
  4. Check whether the used heap memory of JobHistoryServer reaches 80% of the maximum heap memory specified for JobHistoryServer.

  5. On MRS Manager, choose Service > MapReduce > Service Configuration > All > JobHistoryServer > System. Increase the value of -Xmx in the GC_OPTS parameter as required, click Save Configuration, and select Restart the affected services or instance. Click OK to restart the role instance.
  6. Check whether the alarm is cleared.

    • If yes, no further action is required.
    • If no, go to Step 7.

Collect fault information.

  1. On MRS Manager, choose System > Export Log.
  2. Select the following node from the Service drop-down list and click OK.

    • NodeAgent
    • MapReduce

  3. Set Start Time for log collection to 10 minutes ahead of the alarm generation time and End Time to 10 minutes behind the alarm generation time, and click Download.
  4. Contact technical support engineers for help, detail see technical support.

Related Information

N/A