ALM-23004 Loader Heap Memory Usage Exceeds the Threshold

Alarm Description

The system checks the heap memory usage of the Loader service every 60 seconds. This alarm is generated when the heap memory usage of the Loader instance exceeds the threshold for 10 consecutive times. The alarm is cleared when the heap memory usage is less than the threshold.

Alarm Attributes

Alarm Parameters

Impact on the System

Full GC occurs frequently in Loader. The performance deteriorates and page responses are slow. If the memory overflows, Loader may fail to provide services for external systems. The Loader page cannot be accessed, interfaces cannot be called, and active/standby switchover is frequently performed due to exceptions.

Possible Causes

The heap memory usage of the Loader instance is too high or the heap memory is inappropriately allocated.

Handling Procedure

Check heap memory usage.

1. Log in to FusionInsight Manager and choose O&M. In the navigation pane on the left, choose Alarm > Alarms. On the page that is displayed, locate the row containing Loader Heap Memory Usage Exceeds the Threshold, and view the Location information. Check the name of the instance host for which the alarm is generated.
2. On FusionInsight Manager, choose Cluster > Name of the target cluster > Services > Loader and click the Instance tab. On the displayed page, select the role corresponding to the host name for which the alarm is generated and select Customize from the drop-down list in the upper right corner of the chart area. Choose Memory and select Loader Heap Memory Resource Percentage. Click OK.
3. Check whether the heap memory used by Loader reaches the threshold (95% of the maximum heap memory by default).
   • If yes, go to 4.
   • If no, go to 6.

4. On FusionInsight Manager, choose Cluster > Name of the desired cluster > Service > Loader > Configuration, click All Configurations. Search for the GC_OPTS parameter, increase the value of -Xmx as you need, click Save, and click OK.
   

   • If this alarm is generated, the heap memory configured for the current Loader instance is not enough for data transmission. You are advised to open the instance monitoring page, display the Loader heap memory resource status monitoring chart, and observe the change trend of the heap memory used by Loader in the monitoring chart. Then change the value of -Xmx to twice the current heap memory usage or to another value to meet site requirements.
   • When setting the heap memory, you can set -Xms and -Xmx to approximately the same value to prevent performance deterioration caused by heap size adjustment after each GC.
   • The sum of -Xmx and XX:MaxPermSize cannot be greater than the actual physical memory of the node server.

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.

Collect fault information.

6. On FusionInsight Manager, choose O&M. In the navigation pane on the left, choose Log > Download.
7. Expand the Service drop-down list, and select Loader for the target cluster.
8. 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.
9. Contact O&M engineers and provide the collected logs.

Alarm Clearance

This alarm is automatically cleared after the fault is rectified.

Related Information

None.