USER I/O HIGH!!

Question

Hi experts,
SELECT wait_class,
total_waits,
ROUND(100 * (total_waits / sum_waits),2) pct_waits,
time_waited,
ROUND(100 * (time_waited / sum_time),2) pct_time
FROM
(SELECT wait_class,
total_waits,
time_waited
FROM v$system_wait_class
WHERE wait_class != 'Idle'),
(SELECT SUM(total_waits) sum_waits,
SUM(time_waited) sum_time
FROM v$system_wait_class
WHERE wait_class != 'Idle')
ORDER BY 5 DESC;
RESULT:
WAIT_CLASS TOTAL_WAITS PCT_WAITS TIME_WAITED PCT_TIME
User I/O 692,405,365 59.82 273,662,991 85.32
System I/O 75,487,170 6.52 22,839,025 7.12
Commit 62,102,000 5.37 21,343,076 6.65
Application 125,226,754 10.82 2,171,131 .68
Configuration 51,337 .00 407,764 .13
Network 201,685,145 17.43 167,089 .05
Other 231,827 .02 111,851 .03
Concurrency 196,940 .02 57,504 .02
How do I reduce the User I/O?
tks

Answer 1

Since you excluded 'Idle' waits, the rest must be doing actual work. And since the bulk of the work is User I/O, which is what a database is supposed to do, why do you think there is a problem?
Perhaps if you include 'Idle' waits, the figures might look a lot better.