数据库参数准备
db2 create db mydb using codeset utf-8 territory CN
db2 update db cfg using cur_commit DISABLED
db2 get db cfg show detail |grep -i cur
Description Parameter Current Value Delayed Value
Currently Committed (CUR_COMMIT) = DISABLED DISABLED
设置参数CUR_COMMIT=OFF
死锁监视器和数据产生：
未创建监视器前的
db2 list tables for all |grep -i lock
[db2inst1@ora10 ~]$ db2 list tables for all |grep -i lock
LOCKS_HELD SYSIBMADM V 2018-08-25-20.10.48.564505
LOCKWAITS SYSIBMADM V 2018-08-25-20.10.48.568740
SNAPLOCK SYSIBMADM V 2018-08-25-20.10.48.015699
SNAPLOCKWAIT SYSIBMADM V 2018-08-25-20.10.48.046247
1、创建死锁监视器
db2 "create event monitor t_lockinfomation for locking write to unformatted event table"
db2 "set event monitor t_lockinfomation state 1"(记录事件语句）
db2 "select evmonname,EVENT_MON_STATE(evmonname) as state from syscat.eventmonitors"
2、创建死锁
a、准备数据库表
db2 "create table t11 (col char(10))"
db2 "create table t21 (col char(10))"
b、开始进行死锁模拟
打开两个CLP窗口，分别连接到sample库，然后：
在CLP1中执行：
$ db2 +c "insert into t11 values('aaa')"
db2 +c "insert into t33 values('aaa')"
$ 在CLP2中执行：
$ db2 +c "insert into t21 values('bbb')"
执行完插入操作后，在CLP1和CLP2中尽量同步执行以下查询：
在CLP1中执行：
$ db2 +c "select * from t21"
在CLP2中执行：
$ db2 +c "select * from t11"
不用多少时间，就会发现，CLP窗口中报错：
CLP2输出：
$ db2 +c "select * from t11"
SQL0911N The current transaction has been rolled back because of a deadlock
or timeout. Reason code "2". SQLSTATE=40001
3、获取锁等待事件数据
db2 "call EVMON_FORMAT_UE_TO_TABLES ( 'LOCKING', NULL, NULL, NULL, NULL, NULL, 'RECREATE_FORCE', -1, 'SELECT * FROM T_LOCKINFOMATION ORDER BY event_timestamp')"
db2 "set event monitor t_lockinfomation state 0"
db2 list tables for all |grep -i lock
LOCK_ACTIVITY_VALUES DB2INST1 T 2018-08-25-20.53.42.365349
LOCK_EVENT DB2INST1 T 2018-08-25-20.53.41.996997
LOCK_PARTICIPANTS DB2INST1 T 2018-08-25-20.53.42.073427
LOCK_PARTICIPANT_ACTIVITIES DB2INST1 T 2018-08-25-20.53.42.162554
T_LOCKINFOMATION DB2INST1 T 2018-08-25-20.15.24.159899
LOCKS_HELD SYSIBMADM V 2018-08-25-20.10.48.564505
LOCKWAITS SYSIBMADM V 2018-08-25-20.10.48.568740
SNAPLOCK SYSIBMADM V 2018-08-25-20.10.48.015699
SNAPLOCKWAIT SYSIBMADM V 2018-08-25-20.10.48.046247
产生如下表
LOCK_ACTIVITY_VALUES
LOCK_EVENT
LOCK_PARTICIPANTS
LOCK_PARTICIPANT_ACTIVITIES
4、查询死锁相关的语句
db2 "
select c.EVENT_ID,
c.EVENT_TIMESTAMP,
c.EVENT_TYPE,
c.PARTICIPANT_TYPE,
c.APPL_ID,
c.APPL_NAME,
c.AUTH_ID,
c.CLIENT_WRKSTNNAME,
c.LOCK_ESCALATION,
c.LOCK_MODE_REQUESTED,
c.LOCK_MODE,
c.LOCK_OBJECT_TYPE,
c.TABLE_NAME,
c.TABLE_SCHEMA,
d.ACTIVITY_TYPE,
d.PACKAGE_NAME,
d.PACKAGE_SCHEMA,
d.SECTION_NUMBER,
d.EFFECTIVE_ISOLATION,
d.STMT_TEXT
from
(select a.XMLID,
a.EVENT_ID,
a.EVENT_TIMESTAMP,
a.EVENT_TYPE,
b.PARTICIPANT_NO,
b.PARTICIPANT_TYPE,
b.APPL_ID,
b.APPL_NAME,
b.AUTH_ID,
b.CLIENT_WRKSTNNAME,
b.LOCK_NAME,
b.LOCK_ATTRIBUTES,
b.LOCK_ESCALATION,
case (b.LOCK_CURRENT_MODE)
when 0 then 'No Lock'
when 1 then 'IS'
when 2 then 'IX'
when 3 then 'S'
when 4 then 'SIX'
when 5 then 'X'
when 6 then 'IN'
when 7 then 'Z'
when 8 then 'U'
when 9 then 'NS'
when 10 then 'NX'
when 11 then 'W'
when 12 then 'NW' end LOCK_CURRENT_MODE ,
case (b.LOCK_MODE_REQUESTED)
when 0 then 'No Lock'
when 1 then 'IS'
when 2 then 'IX'
when 3 then 'S'
when 4 then 'SIX'
when 5 then 'X'
when 6 then 'IN'
when 7 then 'Z'
when 8 then 'U'
when 9 then 'NS'
when 10 then 'NX'
when 11 then 'W'
when 12 then 'NW' end LOCK_MODE_REQUESTED,
case (b.LOCK_MODE)
when 0 then 'No Lock'
when 1 then 'IS'
when 2 then 'IX'
when 3 then 'S'
when 4 then 'SIX'
when 5 then 'X'
when 6 then 'IN'
when 7 then 'Z'
when 8 then 'U'
when 9 then 'NS'
when 10 then 'NX'
when 11 then 'W'
when 12 then 'NW' end LOCK_MODE,
b.LOCK_OBJECT_TYPE,
b.TABLE_NAME,
b.TABLE_SCHEMA
----b.LOCK_WAIT_START_TIME,
----b.LOCK_WAIT_END_TIME
from LOCK_EVENT a,
LOCK_PARTICIPANTS b
where a.XMLID=b.XMLID) c,
(select e.XMLID,
e.PARTICIPANT_NO,
e.ACTIVITY_TYPE ,
e.PACKAGE_NAME,
e.PACKAGE_SCHEMA,
e.SECTION_NUMBER,
e.EFFECTIVE_ISOLATION,
e.STMT_TEXT
from LOCK_PARTICIPANT_ACTIVITIES e ,
(select XMLID,
PARTICIPANT_NO,
max(ACTIVITY_ID) ACTIVITY_ID
from LOCK_PARTICIPANT_ACTIVITIES
group by XMLID,PARTICIPANT_NO) f
where e.XMLID=f.XMLID and e.PARTICIPANT_NO=f.PARTICIPANT_NO and
e.ACTIVITY_ID=f.ACTIVITY_ID) d
where
c.XMLID=d.XMLID
and c.PARTICIPANT_NO=d.PARTICIPANT_NO
order by c.EVENT_ID "