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DBNAME oracle10g enq:TX contention
10genqueue TX41. enq:TX row lock contention2. enq:TX index
contention3. enq:TX ITL4. enq:TX contention4transaction
contention,enq:TX contentionsessionDMLsesstablespace XXX read
only,session 1:SQL> select sid from v$mystat where rownum select
table_name,tablespace_name from user_tables where
table_name='INFO';TABLE_NAME TABLESPACE_NAME INFO USERSSQL>
update info set note=upper(note);35SQL> ()
session 2:SQL> select sid from v$mystat where rownum alter
tablespace users read only;session 1userssession 2session 3:SQL>
select sid,event,p1,p2,p3 from v$session_wait where sid=148; SID
EVENT
P1 P2 P3
148 enq: TX contention1415053316 65563 166session 2enq: TX
contentionp1,p2,p3SQL> SELECT name, parameter1, parameter2,
parameter3 from v$event_name wherename = 'enq: TX contention';NAME
PARAMETER1 PARAMETER2 PARAMETER3 enq: TX contention name|mode
usn
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148 TX Sharesession 2SQL> select sid from v$session where
taddr in 2 (select b.addr from v$session_wait a,v$transaction b 3
where a.event='enq: TX contention' and trunc(a.p2/power(2,16)) =
xidusn 4 and (bitand(a.p2,to_number('ffff','xxxx'))+0) = xidslot
and a.p3 = xidsqn); SID 145session 2session 1session 21session
2SQL> select
sid,id1,id2,trunc(id1/power(2,16))rbs,bitand(id1,to_number('ffff','xxxx'))+0
slot,id2 seq,lmode,request,type fromv$lock where type = 'TX' and
sid=&sid; sid : 148- 2: from v$lock where type = 'TX' and
sid=&sid 2: from v$lock where type = 'TX' and sid=148 SID ID1
ID2 RBS SLOT SEQ LMODEREQUEST TY 148 65563 166 1 27 166 0
4 TX 148 196646 168 3 38 168 6
0 TX1484(share)ID1ID2v$session_waitp2,p3SQL> select
sid,event,p1,p2,p3 from v$session_wait where sid=148; SID EVENT
P1 P2 P3
148 enq: TX contention1415053316 65563 1662(ID1,ID2)SQL>
select
sid,trunc(id1/power(2,16))rbs,bitand(id1,to_number('ffff','xxxx'))+0
slot,id2 seq,lmode,request from v$lock where type='TX' and
id1=&id1 and id2=&id2; id1 : 65563 id2 : 166- 2: from
v$lock where type='TX' and id1=&id1 and id2=&id2 2: from
v$lock where type='TX' and id1=65563 and id2=166 SID RBS SLOT SEQ
LMODE REQUEST 148 1 27 166 0 4
145 1 27 166 6 0148share145exclusivesession 2RACnode
1sessionSQL> conn test/testConnected.SQL> select sid from
v$mystat where rownum < 2; SID 617
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SQL> insert into info values (1);1 row created.node
2session:SQL> alter tablespace test read only;nodeSQL> select
c.inst_id,c.sidfrom gv$session_wait a,gv$transaction b, gv$session
cwhere a.event='enq: TX contention'and trunc(a.p2/power(2,16)) =
b.xidusnand (bitand(a.p2,to_number('ffff','xxxx'))+0) =
b.xidslotand a.p3 = b.xidsqnand c.taddr = b.addr; INST_ID SID 1
617
