James's Blog

Oracle: perf views

1. v$session_wait : current state view. It lists either the event currently
being waited for or the event last waited for on each session

2. v$session_event: lists the cumulative history of events waited for on each
session. After a session exits, the wait event statistics for that session are
removed from this view.

3. v$system_event: lists the events and times waited for by the whole instance
(that is, all session wait events data rolled up) since instance startup.


v$session_wait is current state view. it also contains a finer-granularity of
information than v$session_event or v$system_event.
it includes additional identifying data for the current event in three parameter
columns: P1, P2 and P3.

posted by James Pei @ 2:27 PM