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徹底搞清楚library cache lock的成因和解決方法（二）
發表于：2007-07-02來源：作者：點擊數：
標簽：
上一個例子中我們主要借助于X$KGLLK基表和event systemstate解決問題，那么如果你不了解X$KGLLK基表，或者忘記了如何使用它，那也不要緊張，這里再介紹一種常規的方法。 從system state 的轉儲信息中，我們已經注意到PROCESS 28當前正在等待@#library cache
上一個例子中我們主要借助于X$KGLLK基表和event systemstate解決問題，那么如果你不了解X$KGLLK基表，或者忘記了如何使用它，那也不要緊張，這里再介紹一種常規的方法。
從system state 的轉儲信息中，我們已經注意到PROCESS 28當前正在等待@#library cache lock@#。
@#handle address@#表示的就是正持有 PROCESS 28 進程所等待的library cache中的地址。
現在我們繼續在跟蹤文件中查找包含 @#handle=c000000122e2a6d8@# 字符串的ORACLE PROCESS，也就是查找blocking session的信息，發現信息如下：
PROCESS 26: ----------------阻塞其他會話的Oracle進程，這里PROCESS 26對應了V$PROCESS中的PID的值
----------------------------------------
SO: c000000109c831e0, type: 2, owner: 0000000000000000, flag: INIT/-/-/0x00
(process) Oracle pid=26, calls cur/top: c00000010b2774d0/c00000010b2774d0, flag: (0) -
int error: 0, call error: 0, sess error: 0, txn error 0
(post info) last post received: 17 24 6
last post received-location: ksusig
last process to post me: c000000109c840f8 25 0
last post sent: 751404 0 15
last post sent-location: ksasnd
last process posted by me: c000000109c836e8 1 6
(latch info) wait_event=0 bits=0
Process Group: DEFAULT, pseudo proc: c000000109eefda0
O/S info: user: ora9i, term: UNKNOWN, ospid: 20552
OSD pid info: Unix process pid: 20552, image: oracle@cs_dc02 (TNS V1-V3)
----------------------------------------
SO: c0000001180b9510, type: 8, owner: c000000109c831e0, flag: INIT/-/-/0x00
(FOB) flags=2 fib ptr=162e1b48 incno=0 pending i/o cnt=0
----------------------------------------
SO: c0000001180b9458, type: 8, owner: c000000109c831e0, flag: INIT/-/-/0x00
(FOB) flags=2 fib ptr=162deb18 incno=0 pending i/o cnt=0
----------------------------------------
SO: c0000001180b8230, type: 8, owner: c000000109c831e0, flag: INIT/-/-/0x00
(FOB) flags=2 fib ptr=162de848 incno=0 pending i/o cnt=0
----------------------------------------
SO: c0000001180b7b00, type: 8, owner: c000000109c831e0, flag: INIT/-/-/0x00
(FOB) flags=2 fib ptr=162de578 incno=0 pending i/o cnt=0
----------------------------------------
SO: c000000108c99e28, type: 4, owner: c000000109c831e0, flag: INIT/-/-/0x00
c000000108c99e28 對應的就是V$SESSION 中的SADDR的值，通過這個信息就可以找到blocking session的SID等信息
(session) trans: c0000001169403c0, creator: c000000109c831e0, flag: (100041) USR/- BSY/-/-/-/-/-
DID: 0002-001A-0000007D, short-term DID: 0000-0000-00000000
txn branch: c00000011b825e18
oct: 0, prv: 0, sql: 800003fb0005f7b0, psql: c00000011fbe3f98, user: 50/PUBUSER
O/S info: user: report16, term: , ospid: 20550, machine: cs_dc02
program: sqlplus@cs_dc02 (TNS V1-V3)
application name: SQL*Plus, hash value=3669949024
waiting for @#SQL*Net message from dblink@# blocking sess=0x0 seq=3319 wait_time=0
driver id=28444553, #bytes=1, =0
-------------------
這里，
#bytes 表示個server process通過database link發送給另一個server process的字節數（bytes）
driver id 是一個10進制數，我們需要把它轉化為16進制數，然后就會發現它對應于我們通過event 10046中的相應的信息：
*** 2005-01-10 11:44:48.200
WAIT #1: nam=@#SQL*Net message from dblink@# ela= 104397696 p1=675562835 p2=1 p3=0
WAIT #1: nam=@#SQL*Net message to dblink@# ela= 4 p1=675562835 p2=1 p3=0
SQL> select to_char(675562835,@#XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX@#) from dual;
TO_CHAR(675562835,@#XXXXXXXXXXXXXX
---------------------------------
28444553
SQL>
temporary object counter: 0
----------------------------------------
SO: c00000011a4496b0, type: 51, owner: c000000108c99e28, flag: INIT/-/-/0x00
LIBRARY OBJECT LOCK: lock=c00000011a4496b0 handle=c00000012029f968 mode=N
call pin=0000000000000000 session pin=c00000011a44ad70
htl=c00000011a449720[c00000011a4baa78,c00000011a4baa78] htb=c00000011a4baa78
user=c000000108c99e28 session=c000000108c99e28 count=1 flags=[00] savepoint=173
LIBRARY OBJECT HANDLE: handle=c00000012029f968
namespace=CRSR flags=RON/KGHP/PN0/[10010000]
kkkk-dddd-llll=0000-0041-0041 lock=N pin=0 latch#=3
lwt=c00000012029f998[c00000012029f998,c00000012029f998] ltm=c00000012029f9a8[c00000012029f9a8,c00000012029f9a8]
pwt=c00000012029f9c8[c00000012029f9c8,c00000012029f9c8] ptm=c00000012029fa58[c00000012029fa58,c00000012029fa58]
ref=c00000012029f978[c0000001202a0068, c0000001202a0068] lnd=c00000012029fa70[c00000012029fa70,c00000012029fa70]
LIBRARY OBJECT: object=c00000012029f5c8
type=CRSR flags=EXS[0001] pflags= [00] status=VALD load=0
DEPENDENCIES: count=1 size=16
AUTHORIZATIONS: count=1 size=16 minimum entrysize=16
ACCESSES: count=1 size=16
DATA BLOCKS:
data# heap pointer status pins change
----- -------- -------- ------ ---- ------
0 c00000012029f8a8 c00000012029f288 I/P/A 0 NONE
6 c00000012029f6e8 c00000012029e7c8 I/-/A 0 NONE
----------------------------------------
。。。 。。。
----------------------------------------
SO: c00000011a44a150, type: 51, owner: c0000001169403c0, flag: INIT/-/-/0x00
////////////// X$KGLLK.KGLLKADR 對應于SO(SO: c00000011a44a150 //////////////
////////////// X$KGLLK.KGLLKUSE 和 x$kgllk.KGLLKSES 對應于owner的值(owner: c0000001169403c0)
LIBRARY OBJECT LOCK: lock=c00000011a44a150 handle=c000000122e2a6d8 mode=X
////////////// X$KGLLK.KGLLKADR 對應于SO 和 lock的值(SO: c00000011a44a150,lock=c00000011a44a150) //////////////
////////////// X$KGLLK.KGLLKHDL 對應于handle的值(handle=c000000122e2a6d8) ////////////////
call pin=0000000000000000 session pin=0000000000000000
////////////// X$KGLLK.KGLLKPNS 對應于session pin的值(session pin=0000000000000000) //////////////
htl=c00000011a44a1c0[c00000011a4bb328,c00000011a4bb328] htb=c00000011a4bb328
user=c000000108c99e28 session=c000000108c99e28 count=1 flags=[00] savepoint=179
user和session的值分別對應著x$kgllk.KGLLKUSE 和 x$kgllk.KGLLKSES，也對應于V$SESSION中阻塞其他會話的SADDR
////////////// X$KGLLK.KGLLKSPN對應于savepoint的值(savepoint=179) //////////////
LIBRARY OBJECT HANDLE: handle=c000000122e2a6d8
name=PUBUSER.CSNOZ629926699966
hash=eddf82b5 timestamp=01-08-2005 13:00:18 previous=NULL
namespace=TABL/PRCD/TYPE flags=KGHP/TIM/PTM/SML/[02000000]
kkkk-dddd-llll=0000-0709-0001 lock=X pin=X latch#=3
lwt=c000000122e2a708[c00000011a449e40,c00000011a449e40] ltm=c000000122e2a718[c000000122e2a718,c000000122e2a718]
pwt=c000000122e2a738[c000000122e2a738,c000000122e2a738] ptm=c000000122e2a7c8[c000000122e2a7c8,c000000122e2a7c8]
ref=c000000122e2a6e8[c000000122e2a6e8, c000000122e2a6e8] lnd=c000000122e2a7e0[c000000122e2a7e0,c000000122e2a7e0]
LOCK INSTANCE LOCK: id=LBcafc8485d0949f81
PIN INSTANCE LOCK: id=NBcafc8485d0949f81 mode=X release=F flags=[00]
LIBRARY OBJECT: object=c000000122e12f70
type=TABL flags=EXS/LOC/CRT[0015] pflags= [00] status=VALD load=0
DATA BLOCKS:
data# heap pointer status pins change
----- -------- -------- ------ ---- ------
0 c000000122e2a618 c000000122e13118 I/P/A 0 INSERT
3 c000000122e13178 0 -/P/- 1 NONE
8 c000000122e12c30 c000000122febdb8 I/P/A 1 UPDATE
9 c000000122e13090 0 -/P/- 1 NONE
10 c000000122e12ce0 c000000122acbc70 I/P/A 1 UPDATE
----------------------------------------
。。。 。。。
根據上述兩個ORACLE進程號(ORACLE PID)，我們可以找到他們的會話信息和操作系統進程信息
SQL> select spid,pid,addr from v$process where pid in (26,28);
SPID PID ADDR
------------ ---------- ----------------
20552 26 C000000109C831E0 ----------- 阻塞其他會話的Oracle進程
22580 28 C000000109C83BF0 ----------- 被阻塞的Oracle進程
SQL>
我們來進一步證實一下上述信息：
SQL>col username for a20
SQL> col osuser for a20
SQL> col machine for a20
SQL> l
1 select sid,serial#,username,osuser,machine,to_char(logon_time,@#yyyy/mm/dd hh24:mi:ss@#) LogonTime
2* from v$session where paddr in ( select addr from v$process where spid =@#&spid@#)
SQL> /
Enter value for spid: 20552 ----------- 阻塞其他會話的Oracle進程
old 2: from v$session where paddr in ( select addr from v$process where spid =@#&spid@#)
new 2: from v$session where paddr in ( select addr from v$process where spid =@#20552@#)
SID SERIAL# USERNAME OSUSER MACHINE LOGONTIME
---------- ---------- -------------------- -------------------- -------------------- -------------------
37 2707 PUBUSER report16 cs_dc02 2005/01/08 13:00:17
SQL> /
Enter value for spid: 22580 ----------- 被阻塞的Oracle進程
old 2: from v$session where paddr in ( select addr from v$process where spid =@#&spid@#)
new 2: from v$session where paddr in ( select addr from v$process where spid =@#22580@#)
SID SERIAL# USERNAME OSUSER MACHINE LOGONTIME
---------- ---------- -------------------- -------------------- -------------------- -------------------
30 24167 PUBUSER ora9i cs_dc02 2005/01/10 10:20:31
SQL> select sid,saddr,paddr,username,status,OSUSER from v$session where sid in (37,30);
SID SADDR PADDR USERNAME STATUS OSUSER
---------- ---------------- ---------------- -------------------- -------- --------------------
30 C000000109F02C68 C000000109C83BF0 PUBUSER ACTIVE ora9i
37 C000000108C99E28 C000000109C831E0 PUBUSER ACTIVE report16
SQL>
現在，問題已經水落石出了，解決方法和方法1中的一樣（在操作系統中直接kill掉相應的操作系統進程）。
當然，處于研究的目的，我們可以進一步了解一下上述兩個會話（SID 30 和 SID 37）所有已經持有鎖的相關信息：
SQL> set linesize 150
SQL> set pages 10000
SQL> select * from v$lock where sid in (37,30);
ADDR KADDR SID TY ID1 ID2 LMODE REQUEST CTIME BLOCK
---------------- ---------------- ---------- -- ---------- ---------- ---------- ---------- ---------- ----------
C0000001169403C0 C000000116940538 37 TX 917507 26579 6 0 180478 2
C00000011676DAE0 C00000011676DB08 37 TM 18 0 3 0 180478 2
C00000010B30C4E8 C00000010B30C508 37 XR 4 0 2 0 180369 2
C00000010B30C460 C00000010B30C480 37 DX 21 0 1 0 68 0
SQL>
不難看出，會話37阻塞了其他會話
現在，我們再進一步看看會話37當前在哪些對象上加了鎖：
SQL> select object_name,object_id from dba_objects where object_id in (@#917507@#,@#18@#,@#4@#,@#21@#) order by object_id;
OBJECT_NAME OBJECT_ID
------------------------------ ----------
TAB$ 4
OBJ$ 18
COL$ 21
SQL> /
OBJECT_NAME OBJECT_ID
------------------------------ ----------
TAB$ 4
OBJ$ 18
COL$ 21
SQL>
接下來，再著重看看SID 為37的會話在library cache中請求和持有對象鎖的詳細信息：
SQL> col KGLNAOBJ for a30
SQL> col USER_NAME for a10
SQL> l
1 select INST_ID,USER_NAME,KGLNAOBJ,KGLLKSNM,KGLLKUSE,KGLLKSES,KGLLKMOD,KGLLKREQ
2* from x$kgllk where KGLLKSNM = 37
SQL> /
INST_ID USER_NAME KGLNAOBJ KGLLKSNM KGLLKUSE KGLLKSES KGLLKMOD KGLLKREQ
---------- ---------- ------------------------------ ---------- ---------------- ---------------- ---------- ----------
2 PUBUSER DBMS_OUTPUT 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER DBMS_OUTPUT 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER DBMS_STANDARD 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER PUBUSER 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER SELECT MINOR_VERSION FROM SY 37 C000000108C99E28 C000000108C99E28 1 0
S.CDC_SYSTEM$
2 PUBUSER SELECT MINOR_VERSION FROM SY 37 C000000108C99E28 C000000108C99E28 1 0
S.CDC_SYSTEM$
2 PUBUSER DBMS_CDC_PUBLISH 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER DBMS_CDC_PUBLISH 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER CSNOZ629926699966 37 C000000108C99E28 C000000108C99E28 3 0
2 PUBUSER DBMS_APPLICATION_INFO 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER DBMS_APPLICATION_INFO 37 C000000108C99E28 C000000108C99E28 1 0
2 PUBUSER DATABASE 37 C000000108C99E28 C000000108C99E28 1 0
12 rows selected.
SQL>
再看看SID為30的會話在library cache中請求和持有對象鎖的詳細信息：
SQL> select INST_ID,USER_NAME,KGLNAOBJ,KGLLKSNM,KGLLKUSE,KGLLKSES,KGLLKMOD,KGLLKREQ
2 from x$kgllk where KGLLKSNM = 30
3 /
INST_ID USER_NAME KGLNAOBJ KGLLKSNM KGLLKUSE KGLLKSES KGLLKMOD KGLLKREQ
---------- ---------- ------------------------------ ---------- ---------------- ---------------- ---------- ----------
2 PUBUSER PUBUSER 30 C000000109F02C68 C000000109F02C68 1 0
2 PUBUSER CSNOZ629926699966 30 C000000109F02C68 C000000109F02C68 0 2
2 PUBUSER DBMS_APPLICATION_INFO 30 C000000109F02C68 C000000109F02C68 1 0
2 PUBUSER DBMS_APPLICATION_INFO 30 C000000109F02C68 C000000109F02C68 1 0
2 PUBUSER DATABASE 30 C000000109F02C68 C000000109F02C68 1 0
SQL>
KGLNAOBJ 列包含了在librarky cache中的對象上執行命令的語句的前80個字符，其實從這里我們也可以大大縮小范圍了
KGLLKSES 對應于V$SESSION 中的 SADDR列的值
KGLLKSNM 對應于V$SESSION 中的SID(Session ID)
KGLLKHDL 的值與方法1中跟蹤文件中的@#handle address@#的值對應
KGLLKPNS 的值對應于方法1中跟蹤文件中的@#Ssession pin@#的值
SQL> set linesize 2000
SQL> l
1 select INST_ID,USER_NAME,KGLNAOBJ,KGLLKSNM,KGLLKUSE,KGLLKSES,KGLLKMOD,KGLLKREQ,KGLLKPNS,KGLLKHDL
2* from x$kgllk where KGLLKSNM in (30,37) order by KGLLKSNM,KGLNAOBJ
SQL> /
INST_ID USER_NAME KGLNAOBJ KGLLKSNM KGLLKUSE KGLLKSES KGLLKMOD KGLLKREQ KGLLKPNS KGLLKHDL
---------- ------------------------------ ------------------------------------------------------------ ---------- ---------------- ---------------- ---------- ---------- ---------------- ----------------
2 PUBUSER DATABASE 30 C000000109F02C68 C000000109F02C68 1 0 00 C000000119F8EC58
2 PUBUSER DBMS_APPLICATION_INFO 30 C000000109F02C68 C000000109F02C68 1 0 00 C00000011CCDDA48
2 PUBUSER DBMS_APPLICATION_INFO 30 C000000109F02C68 C000000109F02C68 1 0 00 C00000011CCD81B8
2 PUBUSER PUBUSER 30 C000000109F02C68 C000000109F02C68 1 0 00 C00000011CBFDAA8
2 PUBUSER CSNOZ629926699966 30 C000000109F02C68 C000000109F02C68 0 2 00 C000000122E2A6D8
2 PUBUSER DATABASE 37 C000000108C99E28 C000000108C99E28 1 0 00 C000000119F8EC58
2 PUBUSER DBMS_APPLICATION_INFO 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011CCDDA48
2 PUBUSER DBMS_APPLICATION_INFO 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011CCD81B8
2 PUBUSER DBMS_CDC_PUBLISH 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011FEA4918
2 PUBUSER DBMS_CDC_PUBLISH 37 C000000108C99E28 C000000108C99E28 1 0 00 C0000001202A4988
2 PUBUSER DBMS_OUTPUT 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011CCB48B0
2 PUBUSER DBMS_OUTPUT 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011FFF5098
2 PUBUSER DBMS_STANDARD 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011CCF0ED8
2 PUBUSER PUBUSER 37 C000000108C99E28 C000000108C99E28 1 0 00 C00000011CBFDAA8
2 PUBUSER SELECT MINOR_VERSION FROM SYS.CDC_SYSTEM$ 37 C000000108C99E28 C000000108C99E28 1 0 C00000011A44AD70 C00000012029F968
2 PUBUSER SELECT MINOR_VERSION FROM SYS.CDC_SYSTEM$ 37 C000000108C99E28 C000000108C99E28 1 0 00 C0000001202A0228
2 PUBUSER CSNOZ629926699966 37 C000000108C99E28 C000000108C99E28 3 0 00 C000000122E2A6D8
17 rows selected.
SQL>
