Answer for LAST EDIT ... of your original question:)
***EDIT***
I guess another way to state this is that I need to know what the collection interval is for Alarms. Are we talking about the 20 sec "Real-Time" interval for collection...
For me its logical that vCenter Alarms using 20 sec "Real-Time" interval for "CPU Ready Time" and other perf statistics otherwise they would be useless ...
Unfortunately I didn't find any official reference also.