Symptoms

Warnings logged in the instance every minute "org.mozilla.javascript.EcmaError: "RrdbStats" is not defined." 

Release

Jakarta and later releases

Cause

The System trigger ' Gather performance stats' is causing this warnings. 

Resolution

*System trigger 'Gather performance stats' can be deleted or disabled to avoid this. 
>> https://<instance-name>.service-now.com/sys_trigger_list.do?sysparm_query=name%3DGather%20performance%20stats