Which two statements are true regarding the Active Session History (ASH) reports for RAC?
A.
They provide details about Oracle databases for all current sessions, and history of past session all RAC nodes.
B.
They provide statistics about Oracle databases for the active sessions on all the RAC nodes.
C.
They report on data captured for active sessions. The volume of data is directly related to the work being performed by sessions.
D.
They report on data captured for active sessions. The volume of data is directly related to the number of sessions on the system.
https://docs.oracle.com/cd/E11882_01/rac.112/e41960/monitor.htm#RACAD7395
Oracle Database records information about active sessions for all active Oracle RAC instances and stores this data in the System Global Area (SGA). Any session that is connected to the database and using CPU is considered an active session. The exception to this is sessions that are waiting for an event that belongs to the idle wait class.
ASH reports present a manageable set of data by capturing only information about active sessions. The amount of the data is directly related to the work being performed, rather than the number of sessions allowed on the system.
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