How can a single ASH sample have 8 sessions with ON CPU status when I have only 2 CPUs in my system?
ASH samples any connected session that is not waiting for some ‘Idle’ wait event. This includes sessions actually using CPU at the time of sampling as well those which are trying to get on the CPU, either because of a new request or end of a previous wait. Therefore, the actual number of sampled sessions could be more than the number of CPUs.