Mục đích: Tìm câu lệnh chiếm tải cao kill, tải ngay lập tức giảm tránh cao tải DB gây timeout ứn dụng
--Top SQL cost cao
SELECT /* order by COST */ inst_id, sql_id,module,parsing_schema_name username,
sql_fulltext sql,
optimizer_cost cost,executions,
ROUND (elapsed_time / executions / 1000000,2) AS "avg"
FROM gv$sqlarea
WHERE optimizer_cost > 2000000
AND last_load_time >= TRUNC (SYSDATE)
AND executions >= 1
AND (elapsed_time / executions/1000000 > 1 )
AND parsing_schema_name NOT LIKE '%SYS%'
ORDER BY optimizer_cost DESC;
SELECT /*Kill theo SQL_ID TOP*/ 'kill -9 ' || SPID A ,a.INST_ID,A.SID,A.SQL_ID, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,BACKGROUND, A.EVENT
FROM gv$session a, gv$process b
WHERE b.ADDR = a.paddr
AND a.inst_id=b.inst_id
--AND B.inst_id = 1
--and a.status='INACTIVE'
--and A.USERNAME LIKE 'BINHTV%'
--AND A.USERNAME not in ('SYS','GGATE','GOLDENGATE','ORA_RECO_070361')
--and a.username not in ('SYS','SYSTEM','SYSMAN','BINHTV','DBSNMP','GGATE','GOLDENGATE'')
--AND a.program LIKE '%rman%'
AND sql_id in (
SELECT sql_id
FROM gv$sqlarea
WHERE optimizer_cost > 2000000
AND last_load_time >= TRUNC (SYSDATE)
AND executions >= 1
AND (elapsed_time / executions/1000000 > 1 )
AND parsing_schema_name NOT LIKE '%SYS%'
)
--and machine like '%HCM%'
--and a.event in ('library cache lock','library cache load lock','library cache: mutex X','cursor: pin S wait on X','library cache pin','library cache lock','library cache: mutex X','gc buffer busy acquire','enq: TS - contention','enq: TX - row lock contention','enq: TM - contention','db file parallel read','row cache lock','enq: DX - contention','enq: US - contention','enq: TX - allocate ITL entry','enq: TX - index contention','enq: SQ - contention','enq: TX - row lock contention','PL/SQL lock timer')
--and round(to_number(sysdate-a.prev_exec_start)*1440) >30
and type='USER'
order by a.inst_id;
Các câu lệnh khác:
/**************************ACTIVE, LOCK **************************/
SELECT /*1.ActiveSession*/ distinct s.inst_id i#, s.username, s.SID SID, s.osuser, s.machine,DECODE(S.WAIT_TIME, 0, S.EVENT, 'CPU') ACTION,
s.sql_id/*,S.PREV_EXEC_START*/, s.logon_time, SUBSTR(DECODE(SS.SQL_TEXT, NULL, AA.NAME, SS.SQL_TEXT), 1, 1000) SQLTEXT,s.p1text, S.P1, s.p2text, S.P2, s.p3text, S.P3
FROM GV$SESSION S, GV$SQLSTATS SS, AUDIT_ACTIONS AA
WHERE
S.STATUS = 'ACTIVE' AND
S.SQL_ID = SS.SQL_ID (+) AND AA.ACTION = S.COMMAND and s.type != 'BACKGROUND' AND S.TYPE = 'USER'
and s.username NOT in ('SYS','SYSMAN','DBSNMP','GGATE','GOLDENGATE','GGADMIN')
--AND username in 'PAYMENT'
--and DECODE(S.WAIT_TIME, 0, S.EVENT, 'CPU') like '%cell single block physical read%'
and lower(ss.sql_text) not like lower('%***%')
--and lower(ss.sql_text) like lower('%SUBSCRIBER_REGISTER')
--and s.sid=5923
--and s.machine like '%BINHTV%'
--and s.sql_id ='ccwg0nqr1zbu7'
ORDER BY username,sql_id
--order by S.PREV_EXEC_START;
;
select /* 2.Total_ActiveSessioins*/ USERNAME,count(*) as "Tong Active Session" from gv$session where status='ACTIVE' group by USERNAME order by count(*) desc;
select /* 3.Total_Session*/ username,status, count(*) "Tong Session" from gv$session group by username,status order by count(*) desc;
Select /*4.Blocking_session*/ inst_id,blocking_session, sid, serial#, sql_id, wait_class, seconds_in_wait, username,STATUS,SCHEMANAME,OSUSER,MACHINE,PROGRAM,TYPE,LOGON_TIME
From gv$session where blocking_session is not NULL and type not like 'BACKGROUND' order by inst_id;
select distinct inst_id,''''|| blocking_session ||''',' from (Select /*4.Blocking_session*/ inst_id,blocking_session, sid, serial#, sql_id, wait_class, seconds_in_wait, username,STATUS,SCHEMANAME,OSUSER,MACHINE,PROGRAM,TYPE,LOGON_TIME
From gv$session where blocking_session is not NULL and type not like 'BACKGROUND' )
order by inst_id;
-- Xac dinh process tu inst_id, status, username, sql_id, machine, event,
SELECT /*username*/ 'kill -9 ' || SPID A ,a.INST_ID,A.SID,A.SQL_ID, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,BACKGROUND, A.EVENT
FROM gv$session a, gv$process b
WHERE b.ADDR = a.paddr
AND a.inst_id=b.inst_id
--AND B.inst_id = 1
--and a.status='INACTIVE'
--and A.USERNAME LIKE 'TRIEUNV%'
--AND A.USERNAME not in ('SYS','GGATE','GOLDENGATE')
--AND a.program LIKE '%rman%'
AND sql_id in ('3nr64fnzfa84z')
--and machine like '%ADMIN%'
--and a.event in ('library cache lock','library cache load lock','library cache: mutex X','cursor: pin S wait on X','library cache pin','library cache lock','library cache: mutex X','gc buffer busy acquire','enq: TS - contention','enq: TX - row lock contention','enq: TM - contention','db file parallel read','row cache lock','enq: DX - contention','enq: US - contention','enq: TX - allocate ITL entry','enq: TX - index contention','enq: SQ - contention','enq: TX - row lock contention','PL/SQL lock timer')
--and round(to_number(sysdate-a.prev_exec_start)*1440) >30
and type='USER'
order by a.inst_id;
SELECT /*5.SID*/ 'kill -9 ' || spid a, a.INST_ID,A.SQL_ID,A.SID, A.SERIAL#, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,a.prev_exec_start,BACKGROUND
FROM gv$session a, gv$process b
WHERE b.addr = a.paddr
AND a.inst_id=b.inst_id
and b.inst_id=2
AND a.sid in (
'4162')
and type='USER'
order by inst_id;
select /*6.SQL_Detail*/ sql_id,sql_fulltext from gv$sql where sql_id in ('184b2tbutgm99');
select distinct sql_ID,
24*60*60*(sysdate - sql_exec_start) seconds_running
FROM v$active_session_history
where sample_time = (select max(sample_time)
from v$active_session_history
where sample_time < to_date('16-09-2021 10:00',
'dd-mm-yyyy hh24:mi'))
and sql_id is not null
order by 24*60*60*(sysdate - sql_exec_start) desc;
select sql_id,sql_fulltext,loaded_versions,executions,loads,invalidations,parse_calls from gv$sql where inst_id=4 and sql_id='16fh6ft7g4jn9S';
SELECT *
FROM GV$SESSION S, GV$SQLSTATS SS, AUDIT_ACTIONS AA
WHERE s.type != 'BACKGROUND' AND S.STATUS = 'ACTIVE' AND S.SQL_ID = SS.SQL_ID (+) AND AA.ACTION = S.COMMAND AND S.TYPE = 'USER'
AND s.sql_id <> (select sql_id from v$session where sid=(select sid from v$mystat where rownum=1)) and username NOT in ('SYS')
and DECODE(S.WAIT_TIME, 0, S.EVENT, 'CPU') IN ('direct path read','db file scattered read','PX Deq Credit: send blkd') ;
SELECT *
FROM GV$SESSION S, GV$SQLSTATS SS, AUDIT_ACTIONS AA
WHERE s.type != 'BACKGROUND' AND S.STATUS = 'ACTIVE' AND S.SQL_ID = SS.SQL_ID (+) AND AA.ACTION = S.COMMAND AND S.TYPE = 'USER' and s.username not in ('SYS','SYSMAN')
and s.event in ('library cache lock','gc buffer busy acquire')
and s.username NOT in ('SYS');
select * from DBA_SCHEDULER_RUNNING_JOBS;
--exec DBMS_SCHEDULER.stop_JOB (job_name => 'SYS.REBUILD_IDX_GGSN',force=>true);
select * from DBA_JOBS_RUNNING;
/**************************SUM *********************************************************/
select /* count , status*/ username,status, count(*) from gv$session group by username,status order by count(*) desc;
select /* Active theo user*/ USERNAME,count(*) from gv$session where status='ACTIVE' group by USERNAME order by count(*) desc;
select status, count(*) from gv$session group by status order by status;
select count(*) from gv$session ;
select USERNAME,count(*) from gv$session group by USERNAME order by count(*) desc;
select machine,count(*) from v$session group by machine order by count(*) desc;
select inst_id, count(*) from gv$session group by inst_id;
select /*Thong ke theo status*/ username,status,count(*) from gv$session where username like 'APP_OWNER%' group by username,status order by count(*) desc;
select /*Thong ke theo inst_id*/ inst_id,count(*), username from gv$session where username like 'APP_OWNER%' group by inst_id, username order by username;
select /* user theo machine */ machine,count(*), username from gv$session where username like 'APP_OWNER%' group by machine, username order by username;
/**************************KILL *********************************************************/
-- Xac dinh process tu inst_id, status, username, sql_id, machine, event,
SELECT /*username*/ 'kill -9 ' || SPID A ,a.INST_ID,A.SID,A.SQL_ID, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,BACKGROUND, A.EVENT
FROM gv$session a, gv$process b
WHERE b.ADDR = a.paddr
AND a.inst_id=b.inst_id
--AND B.inst_id = 1
--and a.status='INACTIVE'
--and A.USERNAME LIKE 'BINHTV%'
--AND A.USERNAME not in ('SYS','GGATE','GOLDENGATE')
--AND a.program LIKE '%rman%'
--AND sql_id in ('gtsw86x47z0au')
and machine like '%crcsrv02%'
and a.event in ('library cache lock','library cache load lock','library cache: mutex X','cursor: pin S wait on X','library cache pin','library cache lock','library cache: mutex X','gc buffer busy acquire','enq: TS - contention','enq: TX - row lock contention','enq: TM - contention','db file parallel read','row cache lock','enq: DX - contention','enq: US - contention','enq: TX - allocate ITL entry','enq: TX - index contention','enq: SQ - contention','enq: TX - row lock contention','PL/SQL lock timer')
--and round(to_number(sysdate-a.prev_exec_start)*1440) >30
and type='USER'
order by a.inst_id;
SELECT /*SID*/ 'kill -9 ' || spid a, a.INST_ID,A.SQL_ID,A.SID, A.SERIAL#, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,a.prev_exec_start,BACKGROUND
FROM gv$session a, gv$process b
WHERE b.addr = a.paddr
AND a.inst_id=b.inst_id
--and b.inst_id=2
AND a.sid in (
13562
)
and type='USER'
and machine not like '%BINHTV%' --and user not like 'SYS'
order by inst_id;
SELECT /*call package*/ 'kill -9 ' || spid a,'alter system kill session ' || '''' || a.sid || ',' || a.SERIAL# || '@' || a.inst_id||'''' || ' immediate;', a.INST_ID,A.SQL_ID,A.SID, A.SERIAL#, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,a.prev_exec_start,BACKGROUND
FROM gv$session a, gv$process b
WHERE b.addr = a.paddr
AND a.inst_id=b.inst_id
--and b.inst_id=4
AND (b.inst_id, a.sid) in (
(select /*+ parallel(8) */ inst_id, sid from gv$access where object like '%PKG_TEST%')
)
and type='USER'
and a.machine not like '%BINHTV%' ;
select *--'alter system kill session ' || '''' || sid || ',' || SERIAL# || '''' || ' immediate;'
select /*+ parallel(8) */ inst_id, sid from gv$access where object like '%TAB1%';
SELECT /*lock table*/ 'kill -9 ' || spid a, a.INST_ID,A.SQL_ID,A.SID, A.SERIAL#, a.USERNAME, a.STATUS,A.SCHEMANAME,a.OSUSER,A.MACHINE,A.PROGRAM,A.TYPE,A.LOGON_TIME,BACKGROUND
FROM gv$session a, gv$process b
WHERE b.addr = a.paddr
AND a.inst_id=b.inst_id
--and b.inst_id=3
AND (b.inst_id, a.sid) in
(SELECT /*+ parallel(8)*/ s.inst_id,s.sid
FROM gv$locked_object v, dba_objects d,
gv$lock l, gv$session s
WHERE v.object_id = d.object_id
AND (v.object_id = l.id1)
AND v.session_id = s.sid
and object_name=upper('TAB1'))
--and type='USER'
--ORDER BY username, session_id;
select /*+ parallel(8) */ sid||','from gv$access where upper(object) like upper('TAB1')
--and inst_id=1;
SELECT v.sid,v.serial#,V.INST_ID,l.ORACLE_USERNAME ora_user, o.object_name, o.object_type,
DECODE(l.locked_mode,0, 'None',1, 'Null', 2, 'Row-S (SS)',3, 'Row-X (SX)',4, 'Share', 5, 'S/Row-X (SSX)',6, 'Exclusive', TO_CHAR(l.locked_mode)) lock_mode,
o.status, to_char(o.last_ddl_time,'dd.mm.yy') last_ddl
FROM dba_objects o, gv$locked_object l, gv$session v
WHERE o.object_id = l.object_id and l.SESSION_ID=v.sid order by 2,3;
-- Xac dinh user dang chay cau lenh SQL nao
select p.INST_ID, 'kill -9 '||P.SPID SPID, s.SID, s.username su, substr(sa.sql_text,1,540) SQL_TEXT
from gv$process p,gv$session s,gv$sqlarea sa
where p.addr=s.paddr and p.INST_ID=s.INST_ID and s.username is not null and s.sql_address=sa.address(+) and s.sql_hash_value=sa.hash_value(+)
and s.username=upper('APP_OWNER')
and type='USER'
order by INST_ID, SID;
--alter system kill session '1066,21548,@1' immediate; /*SID, Serial#*/
--alter system kill session '1921,46696' immediate;
select *--'alter system kill session ' || '''' || sid || ',' || SERIAL# || '''' || ' immediate;'
from gv$session
where event = 'enq: TX - row lock contention'
or event like '%lock contention%';
select 'alter system kill session ' || '''' || sid || ',' || SERIAL# || '''' || ';',TIME_REMAINING+ELAPSED_SECONDS,TIME_REMAINING,TARGET
from v$session_longops a where TIME_REMAINING>0
order by TIME_REMAINING+ELAPSED_SECONDS;
/***************************************************** SQL DETAIL **************************/
select sql_id,sql_fulltext from gv$sql where sql_id in ('67bm8d2ah3xhk');
SELECT /* Tim cau lenh sql */ b.inst_id,b.sid, a.SQL_TEXT, b.username, b.machine, b.blocking_session, B.TYPE
FROM gV$SQLAREA a,gV$SESSION b
WHERE a.ADDRESS = b.SQL_ADDRESS
AND upper(SQL_TEXT) LIKE '%SHOP%';
select machine,username,count(*) from gv$session where sql_id='67bm8d2ah3xhk'
group by machine,username order by count(*) desc;
declare
begin
--SQLs with elapsed time more then 1 hour 155429 155430
SELECT *
FROM dba_hist_snapshot where end_interval_time>=to_date('16/09/2021 09:00:00','dd/mm/yyyy hh24:mi:ss')
and end_interval_time <=to_date('16/09/2021 10:00:00','dd/mm/yyyy hh24:mi:ss')
order by end_interval_time;
--155429 155430
SELECT min(snap_id), max(snap_id)
FROM dba_hist_snapshot where end_interval_time>=to_date('16/09/2021 09:00:00','dd/mm/yyyy hh24:mi:ss')
and end_interval_time <=to_date('16/09/2021 10:00:00','dd/mm/yyyy hh24:mi:ss')
order by end_interval_time;
SELECT sql_id,
text,
elapsed_time,
CPU_TIME,
EXECUTIONS,
PX_SERVERS,
DISK_READ_BYTES,
DISK_WRITE_BYTES,
IO_INTERCONNECT_BYTES,
OFFLOAD_ELIGIBLE_BYTES,
CELL_SMART_SCAN_ONLY_BYTES,
FLASH_CACHE_READS,
ROWS_PROCESSED
--AVG_PX_SERVER
FROM (SELECT x.sql_id,
SUBSTR ( dhst.sql_text, 1, 4000) text,
ROUND ( x.elapsed_time / 1000000,0) elapsed_time,
ROUND ( x.cpu_time / 1000000,0) CPU_TIME,
--ROUND ( x.elapsed_time / 1000000, 3) elapsed_time,
--ROUND ( x.cpu_time / 1000000, 3) cpu_time_sec,
x.executions_delta EXECUTIONS,
ROUND (X.DISK_READ_BYTES/1048576,0) DISK_READ_BYTES,
ROUND (X.DISK_WRITE_BYTES/1048576,0) DISK_WRITE_BYTES,
ROUND (X.IO_INTERCONNECT_BYTES/1048576,0) IO_INTERCONNECT_BYTES,
ROUND (X.OFFLOAD_ELIGIBLE_BYTES/1048576,0) OFFLOAD_ELIGIBLE_BYTES,
X.FLASH_CACHE_READS FLASH_CACHE_READS,
ROUND (X.cell_smart_scan_only_BYTES/1048576,0) CELL_SMART_SCAN_ONLY_BYTES,
(x.ROWS_PROCESSED) ROWS_PROCESSED,
(X.PX_SERVERS) PX_SERVERS,
--ROUND(X.PX_SERVERS/X.executions_delta,0) AVG_PX_SERVER,
row_number () OVER (PARTITION BY x.sql_id ORDER BY 0) rn
FROM dba_hist_sqltext dhst,
(SELECT dhss.sql_id sql_id,
SUM (dhss.cpu_time_delta) cpu_time,
SUM (dhss.elapsed_time_delta) elapsed_time,
SUM (dhss.executions_delta) executions_delta,
SUM (dhss.PHYSICAL_READ_BYTES_DELTA) DISK_READ_BYTES,
SUM (dhss.PHYSICAL_WRITE_BYTES_DELTA) DISK_WRITE_BYTES,
SUM (dhss.IO_INTERCONNECT_BYTES_DELTA) IO_INTERCONNECT_BYTES,
SUM (dhss.IO_OFFLOAD_ELIG_BYTES_DELTA) OFFLOAD_ELIGIBLE_BYTES,
SUM (dhss.OPTIMIZED_PHYSICAL_READS_DELTA) FLASH_CACHE_READS,
SUM (dhss.IO_OFFLOAD_RETURN_BYTES_DELTA) cell_smart_scan_only_BYTES,
SUM (dhss.ROWS_PROCESSED_DELTA) ROWS_PROCESSED,
SUM (dhss.PX_SERVERS_EXECS_DELTA) PX_SERVERS
FROM dba_hist_sqlstat dhss
WHERE dhss.snap_id IN
(SELECT distinct snap_id
FROM dba_hist_snapshot
WHERE SNAP_ID >= 155429 AND SNAP_ID<= 155430)
--comment BELOW line if want to include current executions.
--AND dhss.executions_delta > 0
and dhss.instance_number=1
GROUP BY dhss.sql_id) x
WHERE x.sql_id = dhst.sql_id
AND ROUND ( x.elapsed_time / 1000000, 3) > 3600
)
WHERE rn = 1 ORDER BY ELAPSED_TIME DESC;S
--WAIT_CLASS AND COUNTS / NOTE " NULL VALUE IS CPU"
select wait_class, count(*) cnt from dba_hist_active_sess_history
WHERE SNAP_ID >= 155429 AND SNAP_ID<= 155430
--and instance_number=1
group by wait_class_id, wait_class
order by 2 desc;
-- Top 40 Objects by Physical Read
SELECT * FROM (
SELECT do.OWNER||'.'||do.OBJECT_NAME||'..['||do.OBJECT_TYPE||']' AS OBJECTS,
DHSS.INSTANCE_NUMBER AS INST,
SUM(DHSS.LOGICAL_READS_DELTA) LOGICAL_READ,
SUM(DHSS.PHYSICAL_READS_DELTA) PHY_READ,
SUM(DHSS.PHYSICAL_WRITES_DELTA) PHY_WRIT,
SUM(DHSS.ITL_WAITS_DELTA) ITL_WT,
SUM(DHSS.ROW_LOCK_WAITS_DELTA) ROW_LCK_WT
from dba_hist_seg_stat DHSS, DBA_OBJECTS DO
WHERE DHSS.SNAP_ID >= 155429 AND DHSS.SNAP_ID<= 155430
AND DHSS.OBJ#=DO.OBJECT_ID
and DHSS.INSTANCE_NUMBER=1
group by do.OWNER||'.'||do.OBJECT_NAME||'..['||do.OBJECT_TYPE||']',DHSS.INSTANCE_NUMBER
order BY PHY_READ DESC
) WHERE ROWNUM <=40;
end;
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