ALM-44005 Presto Coordinator Process GC Time Exceeds the Threshold (For MRS 2.x or Earlier)

Description

The system collects GC time of the Presto Coordinator process every 30 seconds. This alarm is generated when the GC time exceeds the threshold (exceeds 5 seconds for three consecutive times). You can change the threshold by choosing System > Configure Alarm Threshold > Service > Presto > Coordinator > Presto Process Garbage Collection Time > Garbage Collection Time of the Coordinator Process on MRS Manager. This alarm is cleared when the Coordinator process GC time is less than or equal to the threshold.

Attribute

Parameter

Impact on the System

If the GC time of the Coordinator process is too long, the Coordinator process running performance will be affected and the Coordinator process will even be unavailable.

Possible Causes

The heap memory of the Coordinator process is overused or inappropriately allocated, causing frequent occurrence of the GC process.

Procedure

1. Check the GC time.
   1. Go to the cluster details page and choose Alarms.
   2. Select the alarm whose Alarm ID is 44005 and view the IP address and role name of the instance in Location.
   3. Choose Components > Presto > Instances > Coordinator (business IP address of the instance for which the alarm is generated) > Customize > Presto Garbage Collection Time. Click OK to view the GC time.
   4. Check whether the GC time of the Coordinator process is longer than 5 seconds.
      • If yes, go to 1.e.
      • If no, go to 2.
   5. Choose Components > Presto > Service Configuration, and switch Basic to All. Choose Presto > Coordinator. Increase the value of -Xmx (maximum heap memory) in the JAVA_OPTS parameter based on the site requirements.
   6. Check whether the alarm is cleared.
      • If yes, no further action is required.
      • If no, go to 2.

2. Collect fault information.
   1. On MRS Manager, choose System > Export Log.
   2. Contact the O&M engineers and send the collected logs.

Reference

None