A few days ago my MacBook Air started running fairly hot with the battery draining quickly. The other issue was that it was impossible to make it sleep. Running it very hot or shutting it down were the only choices since closing the lid or selecting sleep from the Apple menu did not work. I opened Activity Monitor and noticed the powerd process consistently using the CPU around 100%. Unfortunately I didn’t take any screenshots but I will describe the details as best as I can remember them.

After noticing the CPU usage, opening up the Console app revealed hundreds or thousands of error messages being generated by remindd. Then I checked the System Information app and noticed in the power section that it had reminder events in the past that were somehow still showing up there. I had been postponing a reminder for over a week and the date and time in the system info coincided with the initial date of the reminder. I guess my constant postponing triggered some kind of bug in the reminder or power management daemons.

I thought the solution would be easy but I was mistaken. Here is what I tried with multiple reboots:

  • Marked and unmarked the reminder I had been postponing as completed
  • Edited the date for the reminder I had been postponing
  • Deleted the offending reminder
  • Deleted all past completed and future reminders
  • Disabled/re-enabled reminder syncing in iCloud settings
  • Disabled/re-enabled calendar syncing in iCloud settings
  • Toggled multiple power management settings
  • Trashed reminders preferences from Library folders

Unfortunately none of that worked. The only thing that worked was restarting in Recovery mode (Command + R at startup) and reinstalling macOS Catalina. I was running the latest version at the time of writing this, 10.15.5. Just to be safe I reformatted the drive before reinstalling the operating system.

It’s been a couple of days and the MacBook is running better than ever without heating up and low CPU usage when idle. Hopefully that is the end of that problem, fingers crossed. Next time I will think twice about procrastinating when a reminder pops up on my phone or computer.

Screenshot of Reminders App on MacOS Catalina
Reminders App on macOS Catalina