select ss.username, se.SID, VALUE/100 cpu_usage_seconds from v$session ss, v$sesstat se, v$statname sn
where se.STATISTIC# = sn.STATISTIC#
and NAME like ‘%CPU used by this session%’
and se.SID = ss.SID
and ss.status=’ACTIVE’ and ss.username is not null
order by VALUE desc;
Find the CPU usage by session