Help Center/ MapReduce Service/ User Guide/ Alarm Reference (Applicable to MRS 3.x)/ ALM-45590 ConfigNode GC Duration Exceeds the Threshold
Updated on 2024-04-11 GMT+08:00
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ALM-45590 ConfigNode GC Duration Exceeds the Threshold

Alarm Description

The system checks the GC duration of the ConfigNode process every 60 seconds. This alarm is generated when the GC duration exceeds the threshold (12 seconds by default) for three consecutive times. This alarm is cleared when the GC duration is less than the threshold.

You can choose O&M > Alarm > Threshold Configuration > Name of the desired cluster > IoTDB > GC > Total GC duration of ConfigNode process (ConfigNode) to increase the threshold by 20% each time.

Alarm Attributes

Alarm ID

Alarm Severity

Auto Cleared

45590

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

A long GC duration of the ConfigNode process may interrupt services.

Possible Causes

The heap memory configured on the node is improper. As a result, GC occurs frequently.

Handling Procedure

Check the heap memory configuration.

  1. Log in to FusionInsight Manager and choose O&M > Alarm > Alarms. In the real-time alarm list, click in the row containing this alarm and view the role name and instance IP address in Location.
  2. Choose Cluster > Services > IoTDB. Click Instance, click the ConfigNode corresponding to the IP address obtained by 1. Switch to the Dashboard tab page, locate the Total GC Duration of ConfigNode chart, and check whether the GC duration of the ConfigNode process exceeds the threshold.

    If the GC duration of ConfigNode is not displayed, click the drop-down list in the upper right corner of the chart area and choose Customize > GC. In the displayed dialog box, select Total GC Duration of ConfigNode and click OK.

    You can choose O&M > Alarm > Threshold Configuration > Name of the desired cluster > IoTDB > GC > Total GC duration of ConfigNode process (ConfigNode) to view the threshold.

    • If yes, go to 3.
    • If no, go to 6.

  3. Choose Cluster > Services > IoTDB. Click Configurations then All Configurations, click ConfigNode, and choose System. Set -Xmx in GC_OPTS to a larger value and save the configuration.

    • The default value of -Xmx is 2G.
    • If this alarm is occasionally generated, increase the value by 0.5 times. If this alarm is frequently generated, double the value.
    • In the case of large service volume and high service concurrency, you are advised to add instances.

  4. Click Dashboard. Click Restart Service to restart the IoTDB service for the configuration to take effect.
  5. Check whether the alarm is cleared.

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

Collect fault information.

  1. On FusionInsight Manager, choose O&M > Log > Download.
  2. Expand the Service drop-down list, select IoTDB for the target cluster, and click OK.
  3. Expand the Hosts drop-down list. In the Select Host dialog box that is displayed, select the hosts to which the role belongs, and click OK.
  4. Click in the upper right corner, and set Start Date and End Date for log collection to 30 minutes ahead of and after the alarm generation time respectively. Then, click Download.
  5. Contact O&M personnel and provide the collected logs.

Alarm Clearance

This alarm is automatically cleared after the fault is rectified.

Related Information

None