Help Center/ MapReduce Service/ User Guide/ MRS Cluster O&M/ MRS Cluster Alarm Handling Reference/ ALM-18010 ResourceManager GC Time Exceeds the Threshold
Updated on 2024-09-23 GMT+08:00

ALM-18010 ResourceManager GC Time Exceeds the Threshold

Description

The system checks the garbage collection (GC) duration of the ResourceManager process every 60 seconds. This alarm is generated when the GC duration exceeds the threshold (12 seconds by default).

This alarm is cleared when the GC duration is less than the threshold.

Attribute

Alarm ID

Alarm Severity

Automatically Cleared

18010

Major

Yes

Parameters

Name

Meaning

Source

Specifies the cluster for which the alarm is generated.

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

Specifies the threshold triggering the alarm. If the current indicator value exceeds this threshold, the alarm is generated.

Impact on the System

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

Possible Causes

The heap memory of the ResourceManager instance is overused or the heap memory is inappropriately allocated. As a result, GCs occur frequently.

Procedure

Check the GC duration.

  1. On the FusionInsight Manager portal, choose O&M > Alarm > Alarms > ALM-18010 ResourceManager GC Time Exceeds the Threshold > Location to check the IP address of the instance for which the alarm is generated.
  2. On the FusionInsight Manager portal, choose Cluster > Name of the desired cluster > Services > Yarn > Instance > ResourceManager (IP address for which the alarm is generated). Click the drop-down menu in the upper right corner of Chart, choose Customize > Garbage Collection (GC) Time of ResourceManager to check the GC duration statistics of the Broker process collected every minute.

    Figure 1 Garbage Collection (GC) Time of ResourceManager

  3. Check whether the GC duration of the ResourceManager process collected every minute exceeds the threshold (12 seconds by default).

    • If yes, go to 4.
    • If no, go to 7.

  4. On the FusionInsight Manager portal, choose Cluster > Name of the desired cluster > Services > Yarn > Configurations > All Configurations > ResourceManager > System to increase the value of GC_OPTS parameter as required.

    The mapping between the number of NodeManager instances in a cluster and the memory size of ResourceManager is as follows:

    • If the number of NodeManager instances in the cluster reaches 100, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms4G -Xmx4G -XX:NewSize=512M -XX:MaxNewSize=1G
    • If the number of NodeManager instances in the cluster reaches 200, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms6G -Xmx6G -XX:NewSize=512M -XX:MaxNewSize=1G
    • If the number of NodeManager instances in the cluster reaches 500, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms10G -Xmx10G -XX:NewSize=1G -XX:MaxNewSize=2G
    • If the number of NodeManager instances in the cluster reaches 1000, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms20G -Xmx20G -XX:NewSize=1G -XX:MaxNewSize=2G
    • If the number of NodeManager instances in the cluster reaches 2000, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms40G -Xmx40G -XX:NewSize=2G -XX:MaxNewSize=4G
    • If the number of NodeManager instances in the cluster reaches 3000, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms60G -Xmx60G -XX:NewSize=2G -XX:MaxNewSize=4G
    • If the number of NodeManager instances in the cluster reaches 4000, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms80G -Xmx80G -XX:NewSize=2G -XX:MaxNewSize=4G
    • If the number of NodeManager instances in the cluster reaches 5000, the recommended JVM parameters of the ResourceManager instance are as follows: -Xms100G -Xmx100G -XX:NewSize=3G -XX:MaxNewSize=6G

  5. Save the configuration and restart the ResourceManager instance.

    • Restarting the active ResourceManager instance will trigger a active/standby switchover of the ResourceManager instance. During the switchover, Yarn cannot submit new jobs, but submitted jobs are not affected. The Yarn component and components that depend on Yarn generate service unavailable alarms for a short period of time.
    • Restart the standby ResourceManager instance. Services are not affected.

  6. Check whether the alarm is cleared.

    • If yes, no further action is required.
    • If no, go to 7.

Collect fault information.

  1. On the FusionInsight Manager portal, choose O&M > Log > Download.
  2. Select ResourceManager in the required cluster from the Service.
  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 the O&M personnel and send the collected logs.

Alarm Clearing

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

Related Information

None