查看Oracle CPU情况

--发现那些SQL运行了大量的PARSE
     select sql_text, parse_calls, executions from v$sqlarea order by parse_calls desc;
--SYS的总的PARSE情况
     select name, value from v$sysstat where name like 'parse count%';

--CPU空间及繁忙情况
select * from v$osstat;

--查看每个Session的CPU利用情况：
select ss.sid,se.command,ss.value CPU ,se.username,se.program
from v$sesstat ss, v$session se
where ss.statistic# in
(select statistic#
from v$statname
where name = 'CPU used by this session')
and se.sid=ss.sid
and ss.sid>6 order by CPU desc;

--比较一下哪个session的CPU使用时间最多，然后查看该Session的具体情况：
select s.sid, s.event, s.MACHINE,s.OSUSER,s.wait_time, w.seq#, q.sql_text
from v$session_wait w, v$session s, v$process p, v$sqlarea q
where s.paddr=p.addr and
s.sid=&p and
s.sql_address=q.address;
---占用CPU最高的10个Session及其SQL语句
select s.sid,w.wait_time,w.seconds_in_wait,w.state,w.wait_time_micro,w.time_remaining_micro,w.time_since_last_wait_micro,p.USERNAME,
status,server,schemaname,osuser,machine,p.terminal,p.program,logon_time,w.event,w.wait_class,tracefile,sql_text,last_active_time
from v$session_wait w, v$session s, v$process p, v$sqlarea q
where s.paddr=p.addr and
s.sid 
in
( select sid from 
  (
  select ss.sid
  from v$sesstat ss, v$session se
  where ss.statistic# in
  (
     select statistic# from v$statname
     where name = 'CPU used by this session'
  )
  and se.sid=ss.sid and ss.sid>6 order by ss.value desc
  )where rownum<11
)
and s.sql_address=q.address;