FYI: LM can trigger ESXi 6.5 hostd to crash

DO NOT comment out the applies to field on the datasource!  This will remove all historical data - which I can only imagine most of us want to keep.  You can disable the datasource by creating a device group (if you don't have one already) and populating it with all of the ESX hosts. Then, at the group level, select the alert tuning tab and uncheck the box next to the datasource.  This disables polling and alerting, but allows you to keep historical data.