SELECT * FROM (
SELECT
h.event "Wait Event",
SUM(h.wait_time + h.time_waited)/100000 "Total Wait Time"
FROM v$active_session_history h,
v$event_name e
WHERE h.sample_time < (SELECT MAX(sample_time)
FROM v$active_session_history)
AND h.sample_time > (SELECT MAX(sample_time) - 1/24
FROM v$active_session_history)
AND h.event_id = e.event_id
AND e.wait_class <> 'IDLE'
GROUP BY h.event
ORDER BY 2 DESC)
WHERE ROWNUM <=20;
Wait Event | Total Wait Time
---------------------------------------- | ---------------
db file sequential read | 3728.36995
direct path read | 2334.23797
log file sync | 580.71175
cursor: pin S wait on X | 521.31362
read by other session | 356.59181
db file parallel write | 261.61812
direct path write | 232.42318
db file scattered read | 197.4875
direct path write temp | 170.51093
log file parallel write | 145.52274
gc buffer busy acquire | 126.09249
gc current block 2-way | 122.96468
gc current block busy | 84.58933
log file sequential read | 73.03717
gc current grant busy | 69.48569
db file parallel read | 55.68226
reliable message | 54.25905
gc cr grant 2-way | 38.12883
gcs drm freeze in enter server mode | 35.42488
gc cr block busy | 35.39542
Elapsed: 00:00:03.53
SQL>