idea CPU 280% for macbook 10.14.6

Please try to add the following options

-XX:TieredStopAtLevel=1 
-XX:CICompilerCount=2 
-XX:Tier4MinInvocationThreshold=100000 
-XX:Tier4InvocationThreshold=110000 
-XX:Tier4CompileThreshold=120000 

to Help | Edit Custom VM Options.

Let me know if it helps.

问题依旧，我又从新dump下

What do you see in Help | Activity Monitor while the issue is being reproduced?