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  6. ALM-43009 JobHistory GC Time Exceeds the Threshold

ALM-43009 JobHistory GC Time Exceeds the Threshold


The system checks the garbage collection (GC) time of the JobHistory process every 60 seconds. This alarm is generated when the detected GC time exceeds the threshold (exceeds 12 seconds for three consecutive checks.) To change the threshold, choose System > Threshold Configuration > Service > Spark > Garbage Collection (GC) Time of JobHistory > Total GC time in milliseconds. This alarm is cleared when the JobHistory GC time is shorter than or equal to the threshold.


Alarm ID

Alarm Severity

Automatically Cleared








Specifies the service for which the alarm is generated.


Specifies the role for which the alarm is generated.


Specifies the host for which the alarm is generated.

Impact on the System

If the GC time exceeds the threshold, the JobHistory process running performance will be affected and the JobHistory process will even be unavailable.

Possible Causes

The heap memory of the JobHistory process is overused or inappropriately allocated, causing frequent occurrence of the GC process.


  1. Check the GC time.

    1. On MRS Manager, click Alarm and select the alarm whose Alarm ID is 43009. Then check the IP address and role name of the instance in Location.
    2. On MRS Manager, choose Service > Spark > Instance and click the JobHistory for which the alarm is generated to enter the Instance Status page. Then choose Customize > Garbage Collection (GC) Time of JobHistory and click OK.
    3. Check whether the GC time is longer than 12 seconds.
    4. On MRS Manager, choose Service > Spark > Service Configuration, and set Type to All. Choose JobHistory > Default. Increase the value of SPARK_DAEMON_MEMORY as required.
    5. Check whether the alarm is cleared.
      • If yes, no further action is required.
      • If no, go to Step 2.

  2. Collect fault information.

    1. On MRS Manager, choose System > Export Log.
    2. In the Service drop-down list box, select Spark and click OK.
    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.

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