--發現那些sql執行了大量的parse
select sql_text, parse_calls, executions
from v$sqlarea
order by parse_calls desc;
--sys的總的parse情況
select name, value from v$sysstat where name like 'parse count%';
--cpu空間及繁忙情況
select * from v$osstat;
--檢視每個session的cpu利用情況：
select ss.sid, se.command, ss.value cpu, se.username, se.program
from v$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;
--比較一下哪個session的cpu使用時間最多，然後檢視該session的具體情況：
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個session及其sql語句
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;
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