ALM-23006 Loader Direct Memory Usage Exceeds the Threshold

Description

The system checks the direct memory usage of the Loader service every 30 seconds. The alarm is generated when the direct memory usage of a Loader instance exceeds the threshold (80% of the maximum memory) for 5 consecutive times. The alarm is cleared when the direct memory usage of Loader is less than or equal to the threshold.

Attribute

Parameters

Impact on the System

The direct memory overflow may cause a service breakdown.

Possible Causes

The direct memory of the Loader instance is overused or the direct memory is inappropriately allocated.

Procedure

Check direct memory usage.

1. On the MRS Manager portal, choose O&M > Alarm > Alarms > Loader Direct Memory Usage Exceeds the Threshold > Location. Check the host name of the instance involved in this alarm.
2. On the MRS Manager portal, choose Cluster > Name of the desired cluster > Services > Loader > Instance. Click the instance for which the alarm is generated to go to the page for the instance. Click the drop-down menu in the chart area and choose Customize > Memory > Loader Memory Usage Statistics. Click OK.
3. Check whether the used direct memory of Loader reaches the threshold (the default value is 80% of the maximum direct memory) specified for Loader.
   • If yes, go to 4.
   • If no, go to 6.

4. On the MRS Manager portal, choose Cluster > Name of the desired cluster > Services > Loader > Configurations. Click All Configurations. Search LOADER_GC_OPTS in the search box. Increase the value of -XX:MaxDirectMemorySize as required, and click Save. Click OK.
   

   If this alarm is generated, the direct memory configured for the current Loader instance is insufficient for the service scenario. You are advised to open the instance monitoring page, display the Loader direct memory resource status monitoring chart, and observe the change trend of the direct memory used by Loader in the monitoring chart. Then change the value of -XX:MaxDirectMemorySize to twice the current direct memory usage or to another value to meet site requirements.

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 the MRS Manager portal, choose O&M > Log > Download.
7. Select Loader in the required cluster from the Service drop-down list.
8. 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.
9. Contact the O&M personnel and send the collected fault logs.

Alarm Clearing

After the fault is rectified, the system automatically clears this alarm.

Related Information

None