Q: Mac slows down every day 3PM - 6PM
I have mid-2012 MacBook Pro running macOS Sierra.
A few months ago (in El Capitan days) I noticed that my Mac would slow down every day between 3PM and 6PM. Normally it's quite peppy but during those hours it slows down to the point of unusability.
I've been running Activity Monitor and top - u in a terminal to find the culprit but have come up empty handed. The main process is kernel_task which commonly shows %CPU of 500 - even up to over 700 at times. The next processes in the list in terms of CPU utilization vary, and typically use %CPU of 10-20, sometimes more, sometimes less.
This goes on until a bit after 6PM, and then the Mac is zippy again until the next day around 3PM.
I ran a program called Lingon 3 to see if anything was scheduled to run from 3PM - 6PM and nothing was, however I found that it seems to think the default time for its jobs is 3PM (though grayed out because not used). Here's a picture of what I mean: http://cloud.sput.me/hatJ
This is really driving me crazy. I hope someone out there has an idea that can help.
MacBook Pro, macOS Sierra (10.12), 15-inch, Mid 2012
Posted on Sep 27, 2016 9:40 PM