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Updated on 2024-09-23 GMT+08:00
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ALM-45282 UserSync Direct Memory Usage Exceeds the Threshold

Alarm Description

The system checks the direct memory usage of the UserSync service every 60 seconds. This alarm is generated when the direct memory usage of the UserSync instance exceeds the threshold (80% of the maximum memory) for five consecutive times. This alarm is cleared when the UserSync direct memory usage is less than or equal to the threshold.

Alarm Attributes

Alarm ID

Alarm Severity

Auto Cleared

45282

Major

Yes

Alarm Parameters

Parameter

Description

Source

Specifies the cluster for which the alarm was generated.

ServiceName

Specifies the service for which the alarm was generated.

RoleName

Specifies the role for which the alarm was generated.

HostName

Specifies the host for which the alarm was generated.

Trigger Condition

Specifies the threshold for triggering the alarm.

Impact on the System

Direct memory overflow may cause service breakdown.

Possible Causes

The direct memory of the UserSync instance is overused or the direct memory is inappropriately allocated. As a result, the memory usage exceeds the threshold.

Handling Procedure

Check the direct memory usage.

  1. On FusionInsight Manager, choose O&M > Alarm > Alarms > ALM-45282 UserSync Direct Memory Usage Exceeds the Threshold. Check the location information of the alarm. Check the name of the instance host for which the alarm is generated.
  2. On FusionInsight Manager, choose Cluster > Services > Ranger > Instance. Select the role corresponding to the host name of the instance for which the alarm is generated. Click the drop-down list in the upper right corner of the chart area and choose Customize > CPU and Memory > UserSync Direct Memory Usage. Click OK.

    Figure 1 UserSync direct memory usage

  3. Check whether the direct memory used by the UserSync reaches the threshold (80% of the maximum direct memory by default).

    • If yes, go to 4.
    • If no, go to 6.

  4. On FusionInsight Manager, choose Cluster > Services > Ranger > Instance > UserSync > Instance Configuration. Click All Configurations, and choose UserSync > System. Increase the value of -XX:MaxDirectMemorySize in the GC_OPTS parameter based on the site requirements and save the configuration.

    If this alarm is generated, the direct memory configured for UserSync cannot meet the direct memory required by the UserSync process. You are advised to check the direct memory usage of UserSync and change the value of -XX:MaxDirectMemorySize in GC_OPTS to the twice of the direct memory used by UserSync. You can change the value based on the actual service scenario. For details, see 2.

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

    • If yes, no further action is required.
    • If no, go to 6.

      During the service restart, the service is interrupted. During the instance restart, the instance is unavailable, and the task on that instance fails to be executed.

Collect the 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 Ranger for the target cluster.
  3. Click 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 personnel and provide the collected logs.

Alarm Clearance

This alarm is automatically cleared after the fault is rectified.

Related Information

None