So I’ve noticed in Sierra that some of its “helper processes” (apps that run in the background to do various tasks) will occasionally start using 100% CPU for no reason. In particular, I’ve seen the com.apple.appkit.xpc.openAndSavePanelService process stay pegged after a file dialog is done – it just sits there and consumes CPU while doing nothing. Quitting the app that was showing the file dialog will stop the CPU-hogging, but it otherwise continues indefinitely.
I’ve been wondering if this might actually be the source of the much-talked about Consumer Reports findings that the new MacBook Pros have very inconsistent battery life. Their results varied widely from test to test (on the same computer) – maybe one of the WebKit helper processes was just flipping out once in a while due to some underlying bug in Sierra’s interprocess communication or process management services.
While that’s just my own random speculation, the issue of processes running amok seems to be a recurring annoyance to some folks. To help you detect this sort of stuff, I’m adding an option in App Tamer to notify you if a process starts consuming excessive CPU time. If it does, it gives you the options shown in the screenshot.
[…] Update (2017-01-02): Jon Gotow: […]