Oracle死鎖一例(ORA-00060)，鎖表導致的業務死鎖問題

lyong發表於2018-07-05
Oracle

1、問題發現

檢查客戶資料庫的時候發現存在大量死鎖的情況

Thread 1 advanced to log sequence 257 (LGWR switch)
  Current log# 16 seq# 257 mem# 0: /oradata/oracle/online_log/redo16_01.log
  Current log# 16 seq# 257 mem# 1: /oradata/oracle/online_log/redo16_02.log
Tue Jul 03 10:14:53 2018
Archived Log entry 385 added for thread 1 sequence 256 ID 0x59dc8ffa dest 1:
Tue Jul 03 10:14:53 2018
LNS: Standby redo logfile selected for thread 1 sequence 257 for destination LOG_ARCHIVE_DEST_2
Tue Jul 03 10:19:39 2018
opiodr aborting process unknown ospid (23762) as a result of ORA-609
Tue Jul 03 10:51:18 2018
ORA-00060: Deadlock detected. More info in file /u01/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_25846.trc.
Tue Jul 03 10:54:01 2018
ORA-00060: Deadlock detected. More info in file /u01/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_14067.trc.
Tue Jul 03 11:02:28 2018
ORA-00060: Deadlock detected. More info in file /u01/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_20781.trc.
Tue Jul 03 11:21:13 2018
Thread 1 cannot allocate new log, sequence 258
Private strand flush not complete

檢視trace檔案orcl_ora_25846.trc結果如下

Deadlock graph:
                       ---------Blocker(s)--------  ---------Waiter(s)---------
Resource Name          process session holds waits  process session holds waits
TX-026e0020-000001a5       147    4468     X            385     241           S
TM-0007fd6c-00000000       385     241     X            147    4468          SX
  
session 4468: DID 0001-0093-000001FEsession 241: DID 0001-0181-00000014 
session 241: DID 0001-0181-00000014session 4468: DID 0001-0093-000001FE 
  
Rows waited on:
  Session 4468: obj - rowid = 0007FD6C - AAAAAAAAAAAAAAAAAA
  (dictionary objn - 523628, file - 0, block - 0, slot - 0)
  Session 241: no row
  
----- Information for the OTHER waiting sessions -----
Session 241:
  sid: 241 ser: 425 audsid: 24705000 user: 160/FD14
    flags: (0x45) USR/- flags_idl: (0x1) BSY/-/-/-/-/-
    flags2: (0x40009) -/-/INC
  pid: 385 O/S info: user: oracle, term: UNKNOWN, ospid: 20781
    image: oracle@dbserver1
  client details:
    O/S info: user: TL3050, term: TL3050-WZ, ospid: 5300:5348
    machine: WORKGROUPTL3050-WZ program: CWV4.2.8.337_20131204.exe
    application name: CWV4.2.8.337_20131204.exe, hash value=580982453
  current SQL:
  insert into pzd2018
(UNI_NO,ORD,STYPE,STYPE2,SNO,SYEAR,SMONTH,RMONTH,SDAY,SABSTRACT,OPERATOR,J_AMOUNT,D_AMOUNT,SUBJ,SUBJNAME,
OPP_SUBJ,SRC_CODE,ECO_CODE,SRC_PAYTYPE,SRC_BUTYPE,ECO_TYPE,ECO_WARRANT,PRJ_ORDER,PRJ_NAME,OPP_PRJ,CLR_ORDER,
UNIT_CODE,SPECCODE,CONTRACT_NO,CAR_NO,OLPAY_SNO,schedule_date,WB_TYPE,WB_JNUM,WB_DNUM,WB_FACT,NUM_TYPE,
NUM_JNUM,NUM_DNUM,NUM_PRICE,CAP_NO,CAP_ORD,JSFS_CODE,ZPH,BUSS_DATE,OTHER_UNIT,ACNT,BANKNO,ADDRESS1,ADDRESS2,
TNO,ACT_NO,BU_CODE,T_CODE,RESBU_CODE,RESBU_AMT,SPECCODE1,SPECCODE2,SPECCODE3,SPECCODE4,RES_S1,
RES_S2,RES_S3,RES_S4,ASSET_SUBJ,TAX_NO,SRC_NAME,ADDITION,UNI_PRJ_ORDER,Clr_Bu_Code,
Source_Type,Source,SrKey,SMark,Uni_Prj_Name,clrsno,input_name,check_name,attach_act,
attach_act_no,pz_attr,src_type,zj_type,ref_uni_no,charge_sno,charge_name,src_lkx,order_type,c
  
----- End of information for the OTHER waiting sessions -----
  
Information for THIS session:
  
----- Current SQL Statement for this session (sql_id=9ktt36bsngnyx) -----
insert into pz2018
(UNI_NO,STYPE,STYPE2,SNO,SYEAR,SMONTH,RMONTH,SDAY,INPUT_NAME,CHECK_NAME,COMP_NAME,COMP_NAME2,
ADDITION,CHILDNUM,J_AMOUNT,D_AMOUNT,SSTATE,REMARK,PZ_ATTR)
values(:1,:2,:3,:4,:5,:6,:7,:8,:9,:10,:11,:12,:13,:14,:15,:16,:17,:18,:19)
===================================================

2、問題分析

可以看出來241號會話持有一個TM鎖，在執行insert into pzd2018語句在等待S鎖

4468號會話持有一個TX鎖，在執行insert into pz2018語句，在等待SX鎖

通過與業務溝通與資料庫查詢發現了以下的鎖表操作，並和業務確定了屬於業務SQL

lock table pz2018 in exclusive mode

到這裡問題已經清楚了，整個邏輯是這樣的

    241號會話將pz2018全表排他模式進行了鎖定，導致4468會話無法對pz2018表進行insert操作，原因是無法在表上獲取共享排它鎖即SX鎖，導致4468號會話進入等待模式

    而4468號會話在等待前進行了insert into pzd2018操作，而241號會話在插入時存在唯一約束，導致241會話進行TX鎖等待，等待4468號session資料提交或者回滾

這樣一個環狀等待就形成了即死鎖

等待發生時會話的等待情況

SQL> select a.sample_time,
  2         a.session_id,
  3         a.session_serial#,
  4         a.blocking_session bsession,
  5         a.blocking_session_serial# bserial#,
  6         a.event,
  7         a.machine,
  8         a.module,
  9         a.sql_opname
 10    from dba_hist_active_sess_history a
 11   where a.session_id in (241, 4468, 6819, 10817)
 12     and a.sample_time > to_date(`2018070310`, `yyyymmddhh24`)
 13     and a.sample_time < to_date(`2018070312`, `yyyymmddhh24`)
 14     and a.event is not null
 15   order by a.sample_time
 16  ;
SAMPLE_TIME                    SESSION_ID SESSION_SERIAL#   BSESSION   BSERIAL# EVENT                          MACHINE                        MODULE                         SQL_OPNAME
------------------------------ ---------- --------------- ---------- ---------- ------------------------------ ------------------------------ ------------------------------ ----------------------------------------------------------------
03-7月 -18 10.00.40.857 上午          241             425       6587       7875 enq: TM - contention           WORKGROUPTL3050-WZ            CWV4.2.8.337_20131204.exe      LOCK TABLE
03-7月 -18 10.49.45.384 上午        10817              97      12929       7665 read by other session          webserver                      JDBC Thin Client               SELECT
03-7月 -18 10.51.16.143 上午          241             425       4468       2029 enq: TX - row lock contention  WORKGROUPTL3050-WZ            CWV4.2.8.337_20131204.exe      INSERT
03-7月 -18 10.51.16.143 上午         4468            2029        241        425 enq: TM - contention           ZDCWWANGH88208561             XCV5（新5.24）.exe             INSERT
03-7月 -18 10.52.46.903 上午        10817             121                       null event                     dbserver1                                                     SELECT
03-7月 -18 10.53.57.464 上午         6819              99      10817        133 enq: TX - row lock contention  ZDCWWANGWD88981612            CWV4.exe                       INSERT
03-7月 -18 10.53.57.464 上午        10817             133       6819         99 enq: TM - contention           ZDCWWANGH88208561             XCV5（新5.24）.exe             INSERT
03-7月 -18 10.54.07.554 上午        10817             133                       db file parallel read          ZDCWWANGH88208561             XCV5（新5.24）.exe             INSERT
8 rows selected

3、鎖等待的模擬，問題復現

---session1
SQL> lock table pz2018 in exclusive mode;
Table(s) Locked.
----session2
SQL> insert into pzd2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZD_Yong`);
1 row created.
SQL> insert into pz2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZ_Yong`);
----session2執行直接hang住無法完成，在等待TM鎖
SQL> select s.SID,s.BLOCKING_SESSION bsid,s.EVENT,s.MACHINE,s.MODULE,s.STATUS,s.STATE  from  v$session s where s.EVENT is not null and s.STATUS=`ACTIVE` and s.WAIT_CLASS<>`Idle`;
       SID       BSID EVENT                          MACHINE                        MODULE                                   STATUS   STATE
---------- ---------- ------------------------------ ------------------------------ ---------------------------------------- -------- -------------------
        17        143 enq: TM - contention           172-16-8-110                   SQL*Plus                                 ACTIVE   WAITING
----session1執行
SQL> insert into pzd2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZD_Yong`);
--session1 直接hang住，session2丟擲錯誤發現死鎖
SQL> insert into pz2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZ_Yong`);
insert into pz2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZ_Yong`)
*
ERROR at line 1:
ORA-00060: deadlock detected while waiting for resource
----檢查資料庫等待
SQL> set linesize 1000 pagesize 5000
SQL> col EVENT for a30
SQL> col MACHINE for a30
SQL> col MODULE for a40
SQL> select s.SID,s.BLOCKING_SESSION bsid,s.EVENT,s.MACHINE,s.MODULE,s.STATUS,s.STATE  from  v$session s where s.EVENT is not null and s.STATUS=`ACTIVE` and s.WAIT_CLASS<>`Idle`;
       SID       BSID EVENT                          MACHINE                        MODULE                                   STATUS   STATE
---------- ---------- ------------------------------ ------------------------------ ---------------------------------------- -------- -------------------
       143         17 enq: TX - row lock contention  172-16-8-110                   SQL*Plus                                 ACTIVE   WAITING

檢視資料庫alert日誌發現

Thu Jul 05 11:40:40 2018
ORA-00060: Deadlock detected. More info in file /u01/app/oracle/diag/rdbms/dtstack1/dtstack1/trace/dtstack1_ora_29840.trc.

檢視死鎖trace

Deadlock graph:
                       ---------Blocker(s)--------  ---------Waiter(s)---------
Resource Name          process session holds waits  process session holds waits
TM-0001554c-00000000        28      17     X             27     143          SX
TX-00040008-000002d9        27     143     X             28      17           S
  
session 17: DID 0001-001C-00000024      session 143: DID 0001-001B-00000155 
session 143: DID 0001-001B-00000155     session 17: DID 0001-001C-00000024 
  
Rows waited on:
  Session 17: no row
  Session 143: obj - rowid = 0001554C - AAAAAAAAAAAAAAAAAA
  (dictionary objn - 87372, file - 0, block - 0, slot - 0)
  
----- Information for the OTHER waiting sessions -----
Session 143:
  sid: 143 ser: 905 audsid: 610017 user: 85/DTYONG
    flags: (0x45) USR/- flags_idl: (0x1) BSY/-/-/-/-/-
    flags2: (0x40009) -/-/INC
  pid: 27 O/S info: user: oracle, term: UNKNOWN, ospid: 29846
    image: oracle@172-16-8-110 (TNS V1-V3)
  client details:
    O/S info: user: oracle, term: pts/1, ospid: 29845
    machine: 172-16-8-110 program: sqlplus@172-16-8-110 (TNS V1-V3)
    application name: SQL*Plus, hash value=3669949024
  current SQL:
  insert into pz2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZ_Yong`)
  
----- End of information for the OTHER waiting sessions -----
  
Information for THIS session:
  
----- Current SQL Statement for this session (sql_id=7jbgf8fc4cac0) -----
insert into pzd2018(OBJECT_ID,OBJECT_NAME) values(100000000,`PZD_Yong`)
===================================================
PROCESS STATE
-------------
Process global information:
     process: 0x914c4ed0, call: 0x910d2008, xact: 0x90390710, curses: 0x916aa020, usrses: 0x916aa020
     in_exception_handler: no
  ----------------------------------------
  SO: 0x914c4ed0, type: 2, owner: (nil), flag: INIT/-/-/0x00 if: 0x3 c: 0x3
   proc=0x914c4ed0, name=process, file=ksu.h LINE:12721, pg=0
  (process) Oracle pid:28, ser:23, calls cur/top: 0x910d2008/0x910d2008
            flags : (0x0) -
            flags2: (0x0),  flags3: (0x10) 
            intr error: 0, call error: 0, sess error: 0, txn error 0
            intr queue: empty
    ksudlp FALSE at location: 0
  (post info) last post received: 138 0 2
              last post received-location: ksl2.h LINE:2374 ID:kslpsr
              last process to post me: 0x914b3298 1 6
              last post sent: 0 0 26
              last post sent-location: ksa2.h LINE:285 ID:ksasnd
              last process posted by me: 0x914b3298 1 6
    (latch info) wait_event=0 bits=0x0
    Process Group: DEFAULT, pseudo proc: 0x915515e8
    O/S info: user: oracle, term: UNKNOWN, ospid: 29840 
    OSD pid info: Unix process pid: 29840, image: oracle@172-16-8-110 (TNS V1-V3)
    ----------------------------------------
    SO: 0x916aa020, type: 4, owner: 0x914c4ed0, flag: INIT/-/-/0x00 if: 0x3 c: 0x3
     proc=0x914c4ed0, name=session, file=ksu.h LINE:12729, pg=0
    (session) sid: 17 ser: 683 trans: 0x90390710, creator: 0x914c4ed0
              flags: (0x45) USR/- flags_idl: (0x1) BSY/-/-/-/-/-
              flags2: (0x40009) -/-/INC


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