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Oracle: Wait events

-- query following views for wait events
V$SESSION_WAIT V$SESSION_EVENT V$SYSTEM_EVENT

-- V$SESSION_WAIT is a current state view.
it lists either the event currently being waited for or the event last waited
for on each session
-- V$SESSION_EVENT lists the cumulative history of events waited for on each session
After a session exists, the wait event statics for that session are removed from
this view.
-- V$SYSTEM_EVENT lists the events and times waited for by the whole instance
since instance startup

-- timed statistics are automatically collected for database
if the initialization parameter statistics_level is set to typical or all
if STATISTICS is set to BASIC, then you must set TIMED_STATISTICS to TRUE to enable
collection of timed statistics

posted by James Pei @ 5:52 PM