Script To Get Cpu Usage And Wait Event Information In Oracle Database

The below script generates the CPU usage and wait events class information of every minute for last 2 hours. As
this query uses gv$active_session_history, so make sure you have TUNING license pack of oracle
set lines 288
col sample_time for a14
col CONFIGURATION head "CONFIG" for 99.99
col ADMINISTRATIVE head "ADMIN" for 99.99
col OTHER for 99.99
 
SELECT TO_CHAR(SAMPLE_TIME, 'HH24:MI ') AS SAMPLE_TIME,
       ROUND(OTHER / 60, 3) AS OTHER,
       ROUND(CLUST / 60, 3) AS CLUST,
       ROUND(QUEUEING / 60, 3) AS QUEUEING,
       ROUND(NETWORK / 60, 3) AS NETWORK,
       ROUND(ADMINISTRATIVE / 60, 3) AS ADMINISTRATIVE,
       ROUND(CONFIGURATION / 60, 3) AS CONFIGURATION,
       ROUND(COMMIT / 60, 3) AS COMMIT,
       ROUND(APPLICATION / 60, 3) AS APPLICATION,
       ROUND(CONCURRENCY / 60, 3) AS CONCURRENCY,
       ROUND(SIO / 60, 3) AS SYSTEM_IO,
       ROUND(UIO / 60, 3) AS USER_IO,
       ROUND(SCHEDULER / 60, 3) AS SCHEDULER,
       ROUND(CPU / 60, 3) AS CPU,
       ROUND(BCPU / 60, 3) AS BACKGROUND_CPU
  FROM (SELECT TRUNC(SAMPLE_TIME, 'MI') AS SAMPLE_TIME,
               DECODE(SESSION_STATE,
                      'ON CPU',
                      DECODE(SESSION_TYPE, 'BACKGROUND', 'BCPU', 'ON CPU'),
                      WAIT_CLASS) AS WAIT_CLASS
          FROM V$ACTIVE_SESSION_HISTORY
         WHERE SAMPLE_TIME > SYSDATE - INTERVAL '2'
         HOUR
           AND SAMPLE_TIME <= TRUNC(SYSDATE, 'MI')) ASH PIVOT(COUNT(*)
  FOR WAIT_CLASS IN('ON CPU' AS CPU,'BCPU' AS BCPU,
'Scheduler' AS SCHEDULER,
'User I/O' AS UIO,
'System I/O' AS SIO,
'Concurrency' AS CONCURRENCY,
'Application' AS  APPLICATION,
'Commit' AS  COMMIT,
'Configuration' AS CONFIGURATION,
'Administrative' AS   ADMINISTRATIVE,
'Network' AS  NETWORK,
'Queueing' AS   QUEUEING,
'Cluster' AS   CLUST,
'Other' AS  OTHER)) ;


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