For the past couple of weeks, a process identified as usernoted
appeared to "take over" my machine after a few hours of use, eating over 99% of available CPU.
Force quitting the process doesn't help; only a system restart puts usernoted
to sleep for a while.
What is this process and how do I get it under control?
I am running OS X 10.10.5 (build 14F1021).
Best Answer
Usernoted is a process that is responsible for notifications on OS X.
The instructions from this post solved usernoted sitting at 100% CPU on my Mac, even though they were intended to only fix stuck Notification settings:
Next, open the Terminal application. Copy and paste each line of these commands into the Terminal window, in order. Press return after each line:
Close the Terminal app.
For me, the problem started after I had upgraded from Yosemite to El Capitan: usernoted was constantly sitting at 100% CPU and nothing I tried (force-quitting usernoted, checking if Growl or Bark are installed, booting into safe mode, SMC reset, running all the maintenance and cleaning scripts in Onynx, etc.) seemed to help until I tried the steps listed above.