ALM-26054 Heap Memory Usage of Storm Nimbus Exceeds the Threshold (For MRS 2.x or Earlier)

Description

The system checks the heap memory usage of Storm Nimbus every 30 seconds and compares it with the threshold. This alarm is generated if the heap memory usage exceeds the threshold (80% by default).

To modify the threshold, users can choose System > Threshold Configuration > Service > Storm on MRS Manager.

This alarm is cleared if the heap memory usage is lower than or equal to the threshold.

Attribute

Alarm ID	Alarm Severity	Auto Clear
26054	Major	Yes

Parameters

Parameter	Description
ServiceName	Specifies the service for which the alarm is generated.
RoleName	Specifies the role for which the alarm is generated.
HostName	Specifies the host for which the alarm is generated.
Trigger Condition	Generates an alarm when the actual indicator value exceeds the specified threshold.

Impact on the System

Frequent memory garbage collection or memory overflow may occur, affecting submission of Storm services.

Possible Causes

The heap memory usage is high or the heap memory is improperly allocated.

Procedure

Check the heap memory usage.
1. Go to the cluster details page and choose Alarms.
2. Choose ALM-26054 Heap Memory Usage of Storm Nimbus Exceeds the Threshold > Location. Query the HostName of the alarmed instance.
3. Choose Components > Storm > Instances > Nimbus (corresponding to the HostName of the alarmed instance) > Customize > Heap Memory Usage of Nimbus.
4. Check whether the heap memory usage of Nimbus has reached the threshold (80%).
  - If yes, go to 1.e.
  - If no, go to 2.
5. Adjust the heap memory.
  Choose Components > Storm > Service Configuration, and set Type to All. Choose Nimbus > System. Increase the value of -Xmx in NIMBUS_GC_OPTS. Click Save Configuration. Select Restart the affected services or instances and click OK.
6. Check whether the alarm is cleared.
  - If yes, no further action is required.
  - If no, go to 2.
Collect fault information.
1. On MRS Manager, choose System > Export Log.
2. Contact the O&M engineers and send the collected logs.