Dev Log Island

특정 기간 중, CPU 사용율이 높은 쿼리를 조회한다.
CPU 점유율이 높은 쿼리를 찾아서 튜닝하기 위해서 사용한다. 기본적으로 oracle에서 제공하는 view를 활용한다.

사용 테이블

• DBA_HIST_SQLSTAT : SQL Historical Statixtics Information
  DB에서 실행된 SQL에 대한 성능 통계치 view
• DBA_HIST_SNAPSHOT : SnapShot Information
  워크로드 저장소의 스냅샷에 대한 정보 view
• DBA_HIST_SQLTEXT : SQL Text
  워크로드 저장소에 캡쳐된 공유 SQL 커서에 속한 SQL 문의 텍스트 표시.
  이 view는 주로 V$SQL view와 함께 사용됨.

최종 쿼리

  WITH REF_DATE AS (
      /* 대상 기간 지정 */
      SELECT
          TO_DATE('20220401' || ' 000000', 'YYYYMMDD HH24MISS') AS BGN_DE
          , TO_DATE('20230420' || ' 235959', 'YYYYMMDD HH24MISS') AS END_DE
      FROM DUAL
  )
  SELECT
      X.SQL_ID
      , X.CPU_TIME
      , X.EXECUTIONS_DELTA
      , X.CPU_TIME_PER_EXECUTIONS
      , DBMS_LOB.SUBSTR(SUBSTR(D.SQL_TEXT, 1, 200)) AS SQL_TEXT
      , D.SQL_TEXT AS SQL_FULLTEXT
  FROM (
          SELECT
              SQL.DBID
              , SQL.SQL_ID
              , SUM(SQL.CPU_TIME_DELTA) / 1000000 AS CPU_TIME
              , SUM(SQL.EXECUTIONS_DELTA) AS EXECUTIONS_DELTA
              , ROUND((SUM(SQL.CPU_TIME_DELTA) / 1000000) / DECODE(SUM(SQL.EXECUTIONS_DELTA), 0, 1, SUM(SQL.EXECUTIONS_DELTA)) / DECODE(SQL.PX_SERVERS_EXECS_DELTA, 0, 1, SQL.PX_SERVERS_EXECS_DELTA)) AS CPU_TIME_PER_EXECUTIONS
          FROM DBA_HIST_SQLSTAT SQL
              , (
                  SELECT
                      MIN(SNAP_ID) AS START_SNAP_ID
                      , MAX(SNAP_ID) AS END_SNAP_ID
                      , MIN(BEGIN_INTERVAL_TIME) AS BEGIN_INTERVAL_TIME
                      , MAX(END_INTERVAL_TIME) AS END_INTERVAL_TIME
                  FROM DBA_HIST_SNAPSHOT, REF_DATE
                  WHERE BEGIN_INTERVAL_TIME BETWEEN REF_DATE.BGN_DE
                                              AND REF_DATE.END_DE
              ) SNAP
          WHERE SQL.SNAP_ID BETWEEN SNAP.START_SNAP_ID AND SNAP.END_SNAP_ID
          GROUP BY SQL.DBID, SQL.SQL_ID, SQL.PX_SERVERS_EXECS_DELTA
          HAVING SUM(SQL.EXECUTIONS_DELTA) >= 0
          ORDER BY CPU_TIME_PER_EXECUTIONS DESC
  ) X
  INNER JOIN DBA_HIST_SQLTEXT D
      ON D.SQL_ID = X.SQL_ID
      AND D.DBID = X.DBID
  WHERE ROWNUM <= 40
  ;

분리

  SELECT
      SQL.DBID
      , SUM(SQL.CPU_TIME_DELTA) / 1000000 AS CPU_TIME
      , SUM(SQL.EXECUTIONS_DELTA) AS EXECUTIONS_DELTA
      , ROUND((SUM(SQL.CPU_TIME_DELTA) / 1000000) / DECODE(SUM(SQL.EXECUTIONS_DELTA), 0, 1, SUM(SQL.EXECUTIONS_DELTA)) / DECODE(SQL.PX_SERVERS_EXECS_DELTA, 0, 1, SQL.PX_SERVERS_EXECS_DELTA)) AS CPU_TIME_PER_EXECUTIONS
  FROM DBA_HIST_SQLSTAT SQL
      , (
          SELECT
              MIN(SNAP_ID) AS START_SNAP_ID
              , MAX(SNAP_ID) AS END_SNAP_ID
              , MIN(BEGIN_INTERVAL_TIME) AS BEGIN_INTERVAL_TIME
              , MAX(END_INTERVAL_TIME) AS END_INTERVAL_TIME
          FROM DBA_HIST_SNAPSHOT
          WHERE BEGIN_INTERVAL_TIME BETWEEN TO_DATE('20230401' || ' 000000', 'YYYYMMDD HH24MISS')
                                      AND TO_DATE('20230419' || ' 235959', 'YYYYMMDD HH24MISS')
      ) SNAP
  WHERE SQL.SNAP_ID BETWEEN SNAP.START_SNAP_ID AND SNAP.END_SNAP_ID
  GROUP BY SQL.DBID, SQL.SQL_ID, SQL.PX_SERVERS_EXECS_DELTA
  HAVING SUM(SQL.EXECUTIONS_DELTA) >= 0
  ORDER BY CPU_TIME_PER_EXECUTIONS
  ;

  SELECT
      MIN(SNAP_ID) AS START_SNAP_ID
      , MAX(SNAP_ID) AS END_SNAP_ID
      , MIN(BEGIN_INTERVAL_TIME) AS BEGIN_INTERVAL_TIME
      , MAX(END_INTERVAL_TIME) AS END_INTERVAL_TIME
  FROM DBA_HIST_SNAPSHOT
  WHERE BEGIN_INTERVAL_TIME BETWEEN TO_DATE('20230401' || ' 000000', 'YYYYMMDD HH24MISS')
                              AND TO_DATE('20230419' || ' 235959', 'YYYYMMDD HH24MISS')
  ;

-- 락 걸린 테이블 확인
SELECT
    DO.OBJECT_NAME
  , DO.OWNER
  , DO.OBJECT_TYPE
  , DO.OWNER
  , VO.XIDUSN
  , VO.SESSION_ID
  , VO.LOCKED_MODE
FROM
    V$LOCKED_OBJECT VO
  , DBA_OBJECTS DO
WHERE VO.OBJECT_ID = DO.OBJECT_ID
;


-- 해당 테이블에 락이 걸렸는지 확인
SELECT
  A.SID
  , A.SERIAL#
  , B.TYPE
  , C.OBJECT_NAME
FROM
    V$SESSION A
  , V$LOCK B
  , DBA_OBJECTS C
WHERE A.SID = B.SID
  AND B.ID1 = C.OBJECT_ID
  AND B.TYPE='TM'
  AND C.OBJECT_NAME IN (${위 쿼리에서 가져온 OBJECT_NAME});


-- 락 발생 사용자, SQL, OBJECT 조회
SELECT
  DISTINCT X.SESSION_ID
  , A.SERIAL#
  , D.OBJECT_NAME
  , A.MACHINE
  , A.TERMINAL
  , A.PROGRAM
  , B.ADDRESS
  , B.PIECE
  , B.SQL_TEXT
FROM
    V$LOCKED_OBJECT X
  , V$SESSION A
  , V$SQLTEXT B
  , DBA_OBJECTS D
WHERE X.SESSION_ID = A.SID
  AND X.OBJECT_ID = D.OBJECT_ID
  AND A.SQL_ADDRESS = B.ADDRESS 
ORDER BY B.ADDRESS, B.PIECE;


-- 현재 접속자의 SQL 확인 
SELECT
    DISTINCT A.SID
  , A.SERIAL#
  , A.MACHINE
  , A.TERMINAL
  , A.PROGRAM
  , B.ADDRESS
  , B.PIECE
  , B.SQL_TEXT
FROM
    V$SESSION A
  , V$SQLTEXT B
WHERE A.SQL_ADDRESS = B.ADDRESS
ORDER BY A.SID, A.SERIAL#, B.ADDRESS, B.PIECE;


-- 락 세션 죽이기위한 sid 와 serial
SELECT
    A.SID
  , A.SERIAL#
  , A.SID || ', ' || A.SERIAL#
FROM
    V$SESSION A
  , V$LOCK B
  , DBA_OBJECTS C
WHERE A.SID = B.SID
  AND B.ID1 = C.OBJECT_ID
  AND B.TYPE = 'TM'
-- AND C.OBJECT_NAME IN ('${락 걸린 테이블 명}');


-- 해당 세선 kill
SELECT
    DISTINCT X.SESSION_ID
  , A.SERIAL#
  , D.OBJECT_NAME
  , A.MACHINE
  , A.TERMINAL
  , A.PROGRAM
  , A.LOGON_TIME
  , 'ALTER SYSTEM KILL SESSION '''||A.SID||', '||A.SERIAL#||''';'
FROM
    GV$LOCKED_OBJECT X
  , GV$SESSION A
  , DBA_OBJECTS D
WHERE X.SESSION_ID = A.SID
  AND X.OBJECT_ID = D.OBJECT_ID
ORDER BY LOGON_TIME
;


-- 최근 실행된 쿼리 찾기
SELECT 
    SQL_FULLTEXT
  , SQL_ID
  , PARSING_SCHEMA_NAME
  , SERVICE
  , MODULE
  , FIRST_LOAD_TIME
  , LAST_LOAD_TIME
FROM V$SQL
WHERE 1 = 1
  AND PARSING_SCHEMA_NAME = '${스키마 명}'
  AND SERVICE = '${서비스 명}'
ORDER BY LAST_LOAD_TIME DESC
;


-- 최근 실행된 쿼리에 바인팅 변수 찾기
SELECT
    NAME
  , POSITION
  , DATATYPE_STRING
  , VALUE_STRING 
FROM V$SQL_BIND_CAPTURE
WHERE 1=1
  AND SQL_ID = '${위 쿼리에서 가져온 SQL_ID}'
;

SELECT * FROM V$SQL;

SELECT 
  last_active_time
  ,parsing_schema_name
  ,sql_text 
FROM v$sqlarea
WHERE 
  parsing_schema_name <> 'SYS'
  AND parsing_schema_name <> 'SYSMAN'
  AND parsing_schema_name <> 'DBSNMP'
  AND parsing_schema_name <> 'MDSYS'
  AND parsing_schema_name <> 'EXFSYS'
ORDER BY 
  last_active_time DESC;

안타깝게도 어떤 쿼리가 락을 걸었는지는 알기 쉽지 않다.

특히나 Oracle DB S/W update를 주기적으로 하지 않는다면 유지보수가 쉽지 않다.