Q: Random OS freeze or hang after Sierra Upgrade
Since upgrading to Sierra, I've begun experiencing random freezes or hangs of the operating system.
Generally, I retain control of the mouse (connected via trackpad), for at least some period of time. However, only movement is possible -- apps can't be selected, there is no response to clicks, etc. Attempts to switch via cmd+tab produce no results.
I've tried waiting for the system to respond. It eventually slept, then crashed with a wake on sleep failure.
The other response is a hard reset, holding down the power button until a restart is forced.
I've run disk utility in rescue mode, and it reports no problems with the disk. I've not yet tried some of the more esoteric responses like resetting NVRAM and so on...that's probably next. I saw one media report that indicated this problem was happening with El Capitan, and there was no resolution. I'm not sure if this is the same problem carried over, or a new one.
iMac, Mac OS X (10.7.2), 27"
Posted on Sep 24, 2016 6:36 AM