CPU Usage of the vCenter HA witness node VM will be high

Products

• VMware vCenter Server

Issue/Introduction

• After configuring vCenter HA for a long period of time, the CPU usage of the Witness node virtual machine increases
• In the witness node, You can see that the file descriptor of the vmon service process is close to 1024.
  

  root@vcsa [ ~ ]# ps ax | grep vmon
     [process ID] ?        SLl    [time] /usr/lib/vmware-vmon/vmon
  
  root@vcsa [ ~ ]# ls -l /proc/[process ID]/fd | wc -l
  1025

 

 

 

Cause

When vmware-analytics service is down, the num of vmon file discriptors will be increase gradually.
But in the witness node, vmware-analytics service don't up so the increase is not evitable.
Therefore, if the witness node is left running for a long period of time (500 days or more), the file descriptors will run out.

Resolution

Workaround is reboot the witness node to release file descriptors.