When upgrading, test for high CPU usage on SQL
Ran into an issue when upgrading from v1606 to v1610 that the SQL failed to run due to high CPU usage (SQL was being ran on a separate box). Was not noticed until after the upgrade had already started. Maybe one of the pre-req checks for upgrading to SCCM is to look at the average CPU usage by SQL to see if that host will complete the upgrade in a timely manner and reduce the risk of failing.
