V$SYSTEM_EVENT

Oracle 11gR1

V$SYSTEM_EVENT displays information on total waits for an event. Note that the TIME_WAITED and AVERAGE_WAIT columns will contain a value of zero on those platforms that do not support a fast timing mechanism. If you are running on one of these platforms and you want this column to reflect true wait times, you must set TIMED_STATISTICS to TRUE in the parameter file; doing this will have a small negative effect on system performance.

Column	Datatype	Description
EVENT	VARCHAR2(64)	Name of the wait event
TOTAL_WAITS	NUMBER	Total number of waits for the event
TOTAL_TIMEOUTS	NUMBER	Total number of timeouts for the event
TIME_WAITED	NUMBER	Total amount of time waited for the event (in hundredths of a second)
AVERAGE_WAIT	NUMBER	Average amount of time waited for the event (in hundredths of a second)
TIME_WAITED_MICRO	NUMBER	Total amount of time waited for the event (in microseconds)
TOTAL_WAITS_FG	NUMBER	Total number of waits for the event, from foreground sessions
TOTAL_TIMEOUTS_FG	NUMBER	Total number of timeouts for the event, from foreground sessions
TIME_WAITED_FG	NUMBER	Amount of time waited for the event (in hundredths of a second), from foreground sessions
AVERAGE_WAIT_FG	NUMBER	Average amount of time waited for the event (in hundredths of a second), from foreground sessions
TIME_WAITED_MICRO_FG	NUMBER	Amount of time waited for the event (in microseconds), from foreground sessions
EVENT_ID	NUMBER	Identifier of the wait event
WAIT_CLASS_ID	NUMBER	Identifier of the class of the wait event
WAIT_CLASS#	NUMBER	Number of the class of the wait event
WAIT_CLASS	VARCHAR2(64)	Name of the class of the wait event

Note:

1.

select * from V$SYSTEM_EVENT;

EVENT	TOTAL_ WAITS	TOTAL_ TIMEOUTS	TIME_ WAITED	AVERAGE_ WAIT	TIME_ WAITED_ MICRO	EVENT_ID	WAIT_ CLASS_ID	WAIT_ CLASS#	WAIT_ CLASS
pmon timer	1600873	1600437	439734332	274.68	4397343315853	3539483025	2723168908	6	Idle
rdbms ipc message	77206833	15881529	8531684232	110.5	85316842317331	866018717	2723168908	6	Idle
Data file init write	9040	0	6053	0.67	60530787	2326919048	1740759767	8	User I/O
Log archive I/O	17324157	0	467988	0.03	4679881955	2089793129	4108307767	9	System I/O
RMAN backup & recovery I/O	101556208	0	730627	0.01	7306274398	3107297351	4108307767	9	System I/O
class slave wait	2671	3	1701	0.64	17012507	1055154682	2723168908	6	Idle
os thread startup	26235	0	233555	8.9	2335554742	86156091	3875070507	4	Concurrency
SGA: MMAN sleep for component shrink	9272	1376	3222	0.35	32218571	1989349184	2723168908	6	Idle
control file sequential read	45285999	0	2676832	0.06	26768319568	3213517201	4108307767	9	System I/O
……

Oracle dynamic performance views