一、概述
在Oracle數(shù)據(jù)庫(kù)運(yùn)行過程中，我們經(jīng)常會(huì)遇到這樣或那樣的錯(cuò)誤，但是錯(cuò)誤的提示并不具體，加大了我們?cè)谠\斷問題時(shí)的難度。
ErrorStack是Oracle提供的一種對(duì)于錯(cuò)誤堆棧進(jìn)行跟蹤的方法，通過設(shè)置跟蹤可以將一些指定錯(cuò)誤的后臺(tái)信息詳細(xì)的轉(zhuǎn)儲(chǔ)出來，寫入跟蹤文件，幫助我們?cè)\斷問題。
備注：
1、當(dāng)oracle發(fā)生關(guān)鍵的錯(cuò)誤諸如：ora-600,Errorstack是自動(dòng)被oracle dump寫入trace文件中。
2、當(dāng)你在alert.log里面看見這類錯(cuò)誤，并提示已經(jīng)產(chǎn)生trace文件。打開對(duì)應(yīng)的trace后，你會(huì)發(fā)現(xiàn)這類trace文件一般都是以“ksedmp:internal or fatal error"開頭，"kesdmp"意味著Kernel Service Error Dump，這一行下面的內(nèi)容就是errorstack記錄的錯(cuò)誤堆棧！
Errorstack dump也可以通過使用Oradebug errorstack 3手工調(diào)用，前提是先使用Oradebug setospid設(shè)定了目標(biāo)進(jìn)程之后。Oradebug Errorstack對(duì)于診斷一個(gè)session似乎Hang住(但是在v$session_wait里面并未出現(xiàn)合理的wait event)或者是比正常時(shí)消耗更多資源時(shí)，獲取當(dāng)前session執(zhí)行sql、具體的變量值等等信息，從而幫助你找到問題根源！
二、跟蹤級(jí)別和方法
ErrorStack主要有4個(gè)跟蹤級(jí)別，如下
- 0 僅轉(zhuǎn)儲(chǔ)錯(cuò)誤堆棧
- 1 轉(zhuǎn)儲(chǔ)錯(cuò)誤堆棧和函數(shù)調(diào)用堆棧
- 2 Level 1 + ProcessState
- 3 Level 2 + Context area （一般我們?cè)\斷問題，都是使用這個(gè)級(jí)別的跟蹤！）
ErrorStack設(shè)置方法，如下（僅指定特定的錯(cuò)誤代碼，只有這個(gè)特定的錯(cuò)誤出現(xiàn)時(shí)才能被觸發(fā)?。?/span>
- 實(shí)例級(jí)別：alter system set events='984 trace name errorstack forever,level 3' scope=spfile;
- 會(huì)話級(jí)別: alter session set events='984 trace name errorstack forever,level 3';
- oradebug： 1、oradebug setospid xxxx; 2、oradebug dump errorstack 3 --當(dāng)前session正在運(yùn)行的語句
三、ErrorStack跟蹤文件中的內(nèi)容
Errorstack跟蹤文件有很多信息，這里我們主要講解對(duì)我們?cè)\斷問題最有用的四個(gè)部分的內(nèi)容（其它很多內(nèi)容我們無法看懂），如下
- 從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前正在執(zhí)行SQL文本。
- 從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前正在執(zhí)行PL/SQL包和PL/SQL source code line number。
- 從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前bind variable value。
- 從Errorstack跟蹤文件中發(fā)現(xiàn)一個(gè)cursor正在使用多少private memory(UGA)。
針對(duì)上面的四個(gè)部分，我將通過一個(gè)具體的errorstack跟蹤文件示例來展示盒加深理解，errorstack的跟蹤文件如下（具體生成方式代碼，放在最后了）。這一部分的內(nèi)容主要參考tanelpoder大牛的博客。
1、從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前正在執(zhí)行SQL文本
這一部分非常容易找到，當(dāng)前sql語句的文本信息在跟蹤文件的最前面部分(可以搜索Current SQL statement for this session)
Trace file /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
2、從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前正在執(zhí)行PL/SQL包和PL/SQL source code line number
Errorstack跟蹤文件和前面一樣，如下Trace file /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
注意上面跟蹤文件中PL/SQL標(biāo)紅那一部分，就是我們關(guān)注的部分。
如果進(jìn)行errorstack跟蹤式，跟蹤進(jìn)程執(zhí)行的是一個(gè)PL/SQL調(diào)用，那么PL/SQL調(diào)用堆也將被跟蹤下來(在PL/SQL Call Stack部分)。這部分告訴你錯(cuò)誤發(fā)生時(shí)Oracle在執(zhí)行具體哪個(gè)PL/SQL過程（包or函數(shù)）以及errorstack跟蹤過程中的具體哪個(gè)調(diào)用發(fā)生錯(cuò)誤。這對(duì)我們?cè)\斷問題非常有幫助
PL/SQL Call Stack包含三列，如下
- object handle
- line number
- object name
下面我們一一介紹這三列的含義：
1、object handle
object handle是這個(gè)對(duì)象(PL/SQL過程、包、函數(shù)、匿名塊)被load進(jìn)library cache中的內(nèi)存地址，可以通過這個(gè)映射地址和X$KGLOB.KGLHDADR表列關(guān)聯(lián)起來以發(fā)現(xiàn)那個(gè)對(duì)象是正在被處理。如下
SQL> select kglnaown,kglnaobj,kglhdadr from X$KGLOB a where KGLHDADR='00000001075FCD10';
KGLNAOWN KGLNAOBJ KGLHDADR
---------- ---------- ----------------
DBMON P_DH1 00000001075FCD10
2、line number
這個(gè)是非常重要的信息，它將告訴你當(dāng)errorstack調(diào)用發(fā)生時(shí)正在執(zhí)行的PL/SQL代碼（可以定位到代碼中的具體行）。例如，在如上的輸出中，在這個(gè)匿名塊的第1行調(diào)用了DBMON.P_DH2存儲(chǔ)過程，而DBMON.P_DH2存儲(chǔ)過程在第7行調(diào)用了另外一個(gè)存儲(chǔ)過程DBMON.P_DH1，當(dāng)errorstack跟蹤發(fā)生時(shí)正在執(zhí)行DBMON.P_DH2存儲(chǔ)過程中的第6行代碼。
3、object name
PL/SQL存儲(chǔ)的對(duì)象名(或者匿名塊，當(dāng)對(duì)象并沒有存儲(chǔ)在一個(gè)過程中)，如果是匿名塊(匿名塊的文本可以通過V$SQL發(fā)現(xiàn)),你可以關(guān)聯(lián)這個(gè)地址和V$SQL.ADDRESS來發(fā)現(xiàn)匿名塊的文本信息。
以上的PL/SQL call stack僅僅包含三行。
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
應(yīng)該從下而上來閱讀一個(gè)PL/SQL call stack，例如
1.底部的行可以告訴我們正在執(zhí)行一個(gè)匿名塊以及在這個(gè)匿名塊的第一行，它在調(diào)用DBMON.P_DH2存儲(chǔ)過程
2.第二行可以告訴我們DBMON.P_DH2存儲(chǔ)過程在第7行調(diào)用了另外一個(gè)存儲(chǔ)過程DBMON.P_DH1
3.DBMON.P_DH2存儲(chǔ)過程中的第6行代碼出現(xiàn)錯(cuò)誤，errorstack信息被轉(zhuǎn)儲(chǔ)。
通過查詢DBA_SOURCE，我們可以與errorstack跟蹤文件中的PL/SQL call stack部分信息進(jìn)行驗(yàn)證，如下。
SQL> select line, text from dba_source where owner = 'DBMON' and name = 'P_DH2' order by line asc;
LINE TEXT
---------- ------------------------------------------------------------
1 procedure p_dh2 as
2 v_cnt number;
3 begin
4 ----just for errorstack test
5 select count(*) into v_cnt from dh_t;
6 dbms_output.put_line('the dh_t count is '||v_cnt);
7 p_dh1;
8 end;
9
9 rows selected.
SQL> select line, text from dba_source where owner = 'DBMON' and name = 'P_DH1' order by line asc;
LINE TEXT
---------- ------------------------------------------------------------
1 procedure p_dh1 as
2 v_id number :=1234335;
3 v_name varchar2(200) :='oradh';
4 begin
5 --just for errorstack test
6 insert into dh_t values (v_id,v_name);
7 commit;
8 end;
9
9 rows selected.
你可以發(fā)現(xiàn)會(huì)話正在執(zhí)行的PL/SQL第6行（一個(gè)insert語句導(dǎo)致錯(cuò)誤）。
通常,當(dāng)error dump，crash，hang發(fā)生時(shí)(頂部的行是”parent" function遞歸調(diào)用的“child”function正在執(zhí)行的代碼)，PL/SQL errorstack告訴我們精確的PL/SQL code。
3、從Errorstack跟蹤文件中發(fā)現(xiàn)當(dāng)前bind variable value
為什么找到具體的語句后，我們還需要尋找具體的綁定變量值？？可以歸納為如下四種原因
- 一個(gè)會(huì)話可能以某種方式變的非常消耗CPU,并且會(huì)話的wait等待時(shí)間沒有任何意義.
- 你需要調(diào)查什么SQL正在被執(zhí)行，并且你需要查看SQL帶有的綁定變量
- SQL的執(zhí)行計(jì)劃是正常的，但是性能卻非常低下
- 可以假設(shè)當(dāng)某些表或者行源變的大的時(shí)候，存在數(shù)據(jù)傾斜，CBO沒有計(jì)算出正確的執(zhí)行計(jì)劃。
因此，你需要知道當(dāng)問題發(fā)生時(shí)SQL使用的綁定變量是什么，不幸的是Oracle中并沒有一個(gè)V$視圖讓我們?nèi)ゲ榭茨硞€(gè)session的當(dāng)前綁定變量值。V$SQL_BIND_CAPTURE視圖僅僅隨機(jī)的采樣綁定變量值，并不存儲(chǔ)所有的被使用的綁定變量值，而dbms_xplan.display_cursor中顯示的也只是第一次窺探的綁定變量值.
Oracle 11gR2中實(shí)時(shí)的SQL Monitoring特性能夠達(dá)到此目的。在V$SQL_MONITOR中有一列BIND_XML,此列包含正在運(yùn)行的足夠長(zhǎng)時(shí)間(默認(rèn)占用CPU超過5s的SQL，都會(huì)出現(xiàn)在次視圖中)的bind variable values.但是這個(gè)只有在11gR2并且具有Diag+Tuning pack licenses時(shí)才有效。
注意：由于SQL語句的綁定變量值存在于進(jìn)程的PGA中的私有內(nèi)存中，因此不能輕易的跟蹤另一個(gè)進(jìn)程私有內(nèi)存。errorstack跟蹤文件中中包含CURSORDUMP,也就包含我們想要得到的bind variable value。
我們繼續(xù)看開始的跟蹤文件，如下
Trace file /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
ORACLE_HOME = /u01/oracle/product/11.2.0
System name: Linux
Node name: 192oracle.cn100.com
Release: 2.6.32-358.el6.x86_64
Version: #1 SMP Fri Feb 22 00:31:26 UTC 2013
Machine: x86_64
Instance name: cn100
Redo thread mounted by this instance: 1
Oracle process number: 26
Unix process pid: 10848, image: oracle@192oracle.cn100.com (TNS V1-V3)
*** 2014-07-01 11:16:36.260
*** SESSION ID:(61.13360) 2014-07-01 11:16:36.260
*** CLIENT ID:() 2014-07-01 11:16:36.260
*** SERVICE NAME:(SYS$USERS) 2014-07-01 11:16:36.260
*** MODULE NAME:(SQL*Plus) 2014-07-01 11:16:36.260
*** ACTION NAME:() 2014-07-01 11:16:36.260
dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)
----- Error Stack Dump -----
ORA-01438: value larger than specified precision allowed for this column
----- Current SQL Statement for this session (sql_id=b8n03s73k7d39) ----- --可以看到，當(dāng)前SQL就在這一行下面
INSERT INTO DH_T VALUES (:B2 ,:B1 )
----- PL/SQL Stack -----
----- PL/SQL Call Stack -----
object line object
handle number name
0x1075fcd10 6 procedure DBMON.P_DH1
0xfcfaebe8 7 procedure DBMON.P_DH2
0x10e7d6420 1 anonymous block
----- Call Stack Trace -----
calling call entry argument values in hex
location type point (? means dubious value)
-------------------- -------- -------------------- ----------------------------
skdstdst()+36 call kgdsdst() 000000000 ? 000000000 ?
7FFF332C8AD8 ? 000000001 ?
7FFF332CCFD8 ? 000000000 ?
......為了排版,后續(xù)省略......
打開跟蹤文件，通常第一步做的是搜索第一個(gè)"Session Cursor Dump",當(dāng)搜索它的時(shí)候，將看到如下的輸出
----- Session Cursor Dump -----
Current cursor: 2, pgadep=1
Open cursors(pls, sys, hwm, max): 3(1, 1, 64, 1000)
NULL=0 SYNTAX=0 PARSE=0 BOUND=3 FETCH=0 ROW=0
Cached frame pages(total, free):
4k(11, 8), 8k(0, 0), 16k(0, 0), 32k(0, 0)
----- Current Cursor -----
xsc=0x7f5227898580 ctx=0xf92d7aa8 pgactx=0xf92d7aa8 ctxcbk=0xf92d74f8 ctxqbc=(nil) ctxrws=0x10293a4c0
----- Explain Plan Dump -----
----- Compact Format (Stream) -----
Dumping stream from 0 to 22
----------------------------------
0000: 143 137 23 1 1 0 105 0 0 0 1 0 0 0 0 21 9 4 6 7 ......i.............
0020: 0 142 ..
----- Plan Table -----
============
Plan Table
============
--------------------------------------------+-----------------------------------+
| Id | Operation | Name | Rows | Bytes | Cost | Time |
--------------------------------------------+-----------------------------------+
| 0 | INSERT STATEMENT | | | | 1 | |
| 1 | LOAD TABLE CONVENTIONAL | | | | | |
--------------------------------------------+-----------------------------------+
Content of other_xml column
===========================
db_version : 11.2.0.1
parse_schema : DBMON
plan_hash : 0
plan_hash_2 : 0
Compilation Environment Dump
optimizer_mode_hinted = false
optimizer_features_hinted = 0.0.0
parallel_execution_enabled = true
parallel_query_forced_dop = 0
Current cursor: 2, pgadep=1
Open cursors(pls, sys, hwm, max): 3(1, 1, 64, 1000)
NULL=0 SYNTAX=0 PARSE=0 BOUND=3 FETCH=0 ROW=0
Cached frame pages(total, free):
4k(11, 8), 8k(0, 0), 16k(0, 0), 32k(0, 0)
----- Current Cursor -----
xsc=0x7f5227898580 ctx=0xf92d7aa8 pgactx=0xf92d7aa8 ctxcbk=0xf92d74f8 ctxqbc=(nil) ctxrws=0x10293a4c0
----- Explain Plan Dump -----
----- Compact Format (Stream) -----
Dumping stream from 0 to 22
----------------------------------
0000: 143 137 23 1 1 0 105 0 0 0 1 0 0 0 0 21 9 4 6 7 ......i.............
0020: 0 142 ..
----- Plan Table -----
============
Plan Table
============
--------------------------------------------+-----------------------------------+
| Id | Operation | Name | Rows | Bytes | Cost | Time |
--------------------------------------------+-----------------------------------+
| 0 | INSERT STATEMENT | | | | 1 | |
| 1 | LOAD TABLE CONVENTIONAL | | | | | |
--------------------------------------------+-----------------------------------+
Content of other_xml column
===========================
db_version : 11.2.0.1
parse_schema : DBMON
plan_hash : 0
plan_hash_2 : 0
Compilation Environment Dump
optimizer_mode_hinted = false
optimizer_features_hinted = 0.0.0
parallel_execution_enabled = true
parallel_query_forced_dop = 0
......為了排版,后續(xù)省略......
我們可以發(fā)現(xiàn)如下有用的內(nèi)容
- Current cursor: 2,這個(gè)告訴我們?cè)谶@個(gè)會(huì)話的UGA打開的cursor中，當(dāng)前正在執(zhí)行Cursor# 6 游標(biāo)
- the pgadep：1變量告訴我們PGA depth，也就是這個(gè)查詢執(zhí)行的遞歸的深度
如果pgadep為0，它意味著這個(gè)查詢是一個(gè)top-level查詢，正在被用戶或者應(yīng)用通過OCI接口在執(zhí)行。
pgadep為1，意味著它是一個(gè)遞歸的查詢，通過遞歸程序接口(RPI)來執(zhí)行，可能是數(shù)據(jù)字典查詢或者僅僅通過PL/SQL調(diào)用執(zhí)行的SQL。
所以，能夠發(fā)現(xiàn)當(dāng)前正在執(zhí)行的當(dāng)前查詢的綁定變量值，我們需要做的是在trace file中朝前搜索Cursor2#，如下
注意：這個(gè)搜索詞是大小寫敏感的。
Cursor#2(0x7f5227951aa0) state=BOUND curiob=0x7f5227898580
curflg=cd fl2=0 par=(nil) ses=0x129a8edc0
----- Dump Cursor sql_id=b8n03s73k7d39 xsc=0x7f5227898580 cur=0x7f5227951aa0 -----
LibraryHandle: Address=f68ce8d8 Hash=c723b469 LockMode=N PinMode=0 LoadLockMode=0 Status=VALD
ObjectName: Name=INSERT INTO DH_T VALUES (:B2 ,:B1 )
FullHashValue=38f6bac85b76f427b45003c1c723b469 Namespace=SQL AREA(00) Type=CURSOR(00) Identifier=3341005929 OwnerIdn=148
Statistics: InvalidationCount=0 ExecutionCount=1 LoadCount=2 ActiveLocks=1 TotalLockCount=1 TotalPinCount=1
Counters: BrokenCount=1 RevocablePointer=1 KeepDependency=1 KeepHandle=1 BucketInUse=0 HandleInUse=0
Concurrency: DependencyMutex=f68ce988(0, 1, 0, 0) Mutex=f68cea00(61, 19, 0, 6)
Flags=RON/PIN/TIM/PN0/DBN/[10012841]
WaitersLists:
Lock=f68ce968[f68ce968,f68ce968]
Pin=f68ce978[f68ce948,f68ce948]
Timestamp: Current=07-01-2014 11:16:35
LibraryObject: Address=f6b87d18 HeapMask=0000-0001-0001 Flags=EXS[0000] Flags2=[0000] PublicFlags=[0000]
ChildTable: size='16'
Child: id='0' Table=f6b88bc8 Reference=f6b88668 Handle=fab7b4c0
Children:
Child: childNum='0'
LibraryHandle: Address=fab7b4c0 Hash=0 LockMode=N PinMode=S LoadLockMode=0 Status=VALD
Name: Namespace=SQL AREA(00) Type=CURSOR(00)
Statistics: InvalidationCount=0 ExecutionCount=1 LoadCount=1 ActiveLocks=1 TotalLockCount=1 TotalPinCount=2
Counters: BrokenCount=1 RevocablePointer=1 KeepDependency=0 KeepHandle=0 BucketInUse=0 HandleInUse=0
Concurrency: DependencyMutex=fab7b570(0, 0, 0, 0) Mutex=f68cea00(61, 19, 0, 6)
Flags=RON/PIN/PN0/EXP/[10012111]
WaitersLists:
Lock=fab7b550[fab7b550,fab7b550]
Pin=fab7b560[fab7b530,fab7b530]
LibraryObject: Address=f6569b20 HeapMask=0000-0001-0001 Flags=EXS[0000] Flags2=[0000] PublicFlags=[0000]
DataBlocks:
Block: #='0' name=CCUR^c723b469 pins=0 Change=NONE
Heap=f6a0b38 Pointer=f6569c08 Extent=f6569aa0 Flags=I/-/P/A/-/-
FreedLocation=0 Alloc=3.093750 Size=3.937500 LoadTime=11473268840
Block: #='6' name=SQLA^c723b469 pins=0 Change=NONE
Heap=f6b88438 Pointer=f92d7aa8 Extent=f92d6e48 Flags=I/-/P/A/-/E
FreedLocation=0 Alloc=8.890625 Size=11.859375 LoadTime=0
NamespaceDump:
Child Cursor: Heap0=0xf6569c08 Heap6=0xf92d7aa8 Heap0 Load Time=07-01-2014 11:16:35 Heap6 Load Time=07-01-2014 11:16:35
NamespaceDump:
Parent Cursor: sql_id=b8n03s73k7d39 parent=0xf6b87e00 maxchild=1 plk=y ppn=n kkscs=0xf6b88308 nxt=(nil) flg=18 cld=0 hd=0xfab7b4c0 par=0xf6b87e00
Mutex 0xf6b88308(0, 0) idn 3000000000
ct=0 hsh=0 unp=(nil) unn=0 hvl=f6b88c60 nhv=0 ses=(nil)
hep=0xf6b88398 flg=80 ld=1 ob=0xf6569b20 ptr=0xf92d7aa8 fex=0xf92d6e48
cursor instantiation=0x7f5227898580 used=1404184595 exec_id=16777216 exec=1
child#0(0xfab7b4c0) pcs=0xf6b88308
clk=0x10d6111e0 ci=0xf6569c08 pn=0xfdf4c890 ctx=0xf92d7aa8
kgsccflg=1 llk[0x7f5227898588,0x7f5227898588] idx=6a
xscflg=c0110676 fl2=d120000 fl3=422a2188 fl4=100
----- Bind Byte Code (IN) -----
Opcode = 6 Bind Rpi Scalar Sql In(may be out) Nocopy NoSkip
Offsi = 48, Offsi = 0
Opcode = 6 Bind Rpi Scalar Sql In(may be out) Nocopy NoSkip
Offsi = 48, Offsi = 32
----- Bind Info (kkscoacd) -----
Bind#0
oacdty=02 mxl=22(21) mxlc=00 mal=00 scl=00 pre=00
oacflg=13 fl2=206001 frm=00 csi=00 siz=24 off=0
kxsbbbfp=7f5227943d08 bln=22 avl=05 flg=09
value=1234335
Bind#1
oacdty=01 mxl=2000(200) mxlc=00 mal=00 scl=00 pre=00
oacflg=13 fl2=206001 frm=01 csi=852 siz=2000 off=0
kxsbbbfp=7f5227943d48 bln=2000 avl=05 flg=09
value="oradh"
Frames pfr 0x7f5227897c18 siz=3424 efr 0x7f5227897b38 siz=3376
Cursor frame dump
enxt: 3.0x00000550 enxt: 2.0x00000040 enxt: 1.0x000007a0
pnxt: 1.0x00000030
kxscphp=0x7f5227961030 siz=984 inu=584 nps=360
kxscbhp=0x7f5227961920 siz=984 inu=152 nps=0
kxscwhp=0x7f5227960f40 siz=4056 inu=56 nps=0
curflg=cd fl2=0 par=(nil) ses=0x129a8edc0
----- Dump Cursor sql_id=b8n03s73k7d39 xsc=0x7f5227898580 cur=0x7f5227951aa0 -----
LibraryHandle: Address=f68ce8d8 Hash=c723b469 LockMode=N PinMode=0 LoadLockMode=0 Status=VALD
ObjectName: Name=INSERT INTO DH_T VALUES (:B2 ,:B1 )
FullHashValue=38f6bac85b76f427b45003c1c723b469 Namespace=SQL AREA(00) Type=CURSOR(00) Identifier=3341005929 OwnerIdn=148
Statistics: InvalidationCount=0 ExecutionCount=1 LoadCount=2 ActiveLocks=1 TotalLockCount=1 TotalPinCount=1
Counters: BrokenCount=1 RevocablePointer=1 KeepDependency=1 KeepHandle=1 BucketInUse=0 HandleInUse=0
Concurrency: DependencyMutex=f68ce988(0, 1, 0, 0) Mutex=f68cea00(61, 19, 0, 6)
Flags=RON/PIN/TIM/PN0/DBN/[10012841]
WaitersLists:
Lock=f68ce968[f68ce968,f68ce968]
Pin=f68ce978[f68ce948,f68ce948]
Timestamp: Current=07-01-2014 11:16:35
LibraryObject: Address=f6b87d18 HeapMask=0000-0001-0001 Flags=EXS[0000] Flags2=[0000] PublicFlags=[0000]
ChildTable: size='16'
Child: id='0' Table=f6b88bc8 Reference=f6b88668 Handle=fab7b4c0
Children:
Child: childNum='0'
LibraryHandle: Address=fab7b4c0 Hash=0 LockMode=N PinMode=S LoadLockMode=0 Status=VALD
Name: Namespace=SQL AREA(00) Type=CURSOR(00)
Statistics: InvalidationCount=0 ExecutionCount=1 LoadCount=1 ActiveLocks=1 TotalLockCount=1 TotalPinCount=2
Counters: BrokenCount=1 RevocablePointer=1 KeepDependency=0 KeepHandle=0 BucketInUse=0 HandleInUse=0
Concurrency: DependencyMutex=fab7b570(0, 0, 0, 0) Mutex=f68cea00(61, 19, 0, 6)
Flags=RON/PIN/PN0/EXP/[10012111]
WaitersLists:
Lock=fab7b550[fab7b550,fab7b550]
Pin=fab7b560[fab7b530,fab7b530]
LibraryObject: Address=f6569b20 HeapMask=0000-0001-0001 Flags=EXS[0000] Flags2=[0000] PublicFlags=[0000]
DataBlocks:
Block: #='0' name=CCUR^c723b469 pins=0 Change=NONE
Heap=f6a0b38 Pointer=f6569c08 Extent=f6569aa0 Flags=I/-/P/A/-/-
FreedLocation=0 Alloc=3.093750 Size=3.937500 LoadTime=11473268840
Block: #='6' name=SQLA^c723b469 pins=0 Change=NONE
Heap=f6b88438 Pointer=f92d7aa8 Extent=f92d6e48 Flags=I/-/P/A/-/E
FreedLocation=0 Alloc=8.890625 Size=11.859375 LoadTime=0
NamespaceDump:
Child Cursor: Heap0=0xf6569c08 Heap6=0xf92d7aa8 Heap0 Load Time=07-01-2014 11:16:35 Heap6 Load Time=07-01-2014 11:16:35
NamespaceDump:
Parent Cursor: sql_id=b8n03s73k7d39 parent=0xf6b87e00 maxchild=1 plk=y ppn=n kkscs=0xf6b88308 nxt=(nil) flg=18 cld=0 hd=0xfab7b4c0 par=0xf6b87e00
Mutex 0xf6b88308(0, 0) idn 3000000000
ct=0 hsh=0 unp=(nil) unn=0 hvl=f6b88c60 nhv=0 ses=(nil)
hep=0xf6b88398 flg=80 ld=1 ob=0xf6569b20 ptr=0xf92d7aa8 fex=0xf92d6e48
cursor instantiation=0x7f5227898580 used=1404184595 exec_id=16777216 exec=1
child#0(0xfab7b4c0) pcs=0xf6b88308
clk=0x10d6111e0 ci=0xf6569c08 pn=0xfdf4c890 ctx=0xf92d7aa8
kgsccflg=1 llk[0x7f5227898588,0x7f5227898588] idx=6a
xscflg=c0110676 fl2=d120000 fl3=422a2188 fl4=100
----- Bind Byte Code (IN) -----
Opcode = 6 Bind Rpi Scalar Sql In(may be out) Nocopy NoSkip
Offsi = 48, Offsi = 0
Opcode = 6 Bind Rpi Scalar Sql In(may be out) Nocopy NoSkip
Offsi = 48, Offsi = 32
----- Bind Info (kkscoacd) -----
Bind#0
oacdty=02 mxl=22(21) mxlc=00 mal=00 scl=00 pre=00
oacflg=13 fl2=206001 frm=00 csi=00 siz=24 off=0
kxsbbbfp=7f5227943d08 bln=22 avl=05 flg=09
value=1234335
Bind#1
oacdty=01 mxl=2000(200) mxlc=00 mal=00 scl=00 pre=00
oacflg=13 fl2=206001 frm=01 csi=852 siz=2000 off=0
kxsbbbfp=7f5227943d48 bln=2000 avl=05 flg=09
value="oradh"
Frames pfr 0x7f5227897c18 siz=3424 efr 0x7f5227897b38 siz=3376
Cursor frame dump
enxt: 3.0x00000550 enxt: 2.0x00000040 enxt: 1.0x000007a0
pnxt: 1.0x00000030
kxscphp=0x7f5227961030 siz=984 inu=584 nps=360
kxscbhp=0x7f5227961920 siz=984 inu=152 nps=0
kxscwhp=0x7f5227960f40 siz=4056 inu=56 nps=0
注意：重點(diǎn)關(guān)注上面標(biāo)紅字體部份
ErrorStack dump是我們可以很可靠的找到SQL語句當(dāng)前使用的綁定變量值一種方法。另外，還有如下說明：
- 在errorstack跟蹤文件中發(fā)現(xiàn)Cursor#2，它的state=BOUND，意味著綁定變量值已經(jīng)被賦予的
- SQL文本是我們?cè)谇懊嬉呀?jīng)查找出來的，我們可以看到兩個(gè)綁定變量值
- Bind variale numbering是從0開始，所以如果我們想搜索第一個(gè)綁定值，需要搜索Bind#0
4、從Errorstack跟蹤文件中發(fā)現(xiàn)一個(gè)cursor正在使用多少private memory(UGA)
繼續(xù)我們前面的示例，跟蹤文件中能夠度量一個(gè)session的某些游標(biāo)使用了多少UGA私有內(nèi)存。如下
Cursor#2游標(biāo)部分：
Cursor frame dump
enxt: 3.0x00000550 enxt: 2.0x00000040 enxt: 1.0x000007a0
pnxt: 1.0x00000030
kxscphp=0x7f5227961030 siz=984 inu=584 nps=360
kxscbhp=0x7f5227961920 siz=984 inu=152 nps=0
kxscwhp=0x7f5227960f40 siz=4056 inu=56 nps=0
Cursor#1游標(biāo)部分：
Cursor frame dump
enxt: 12.0x000005c0 enxt: 11.0x00000fd8 enxt: 10.0x00000fa0 enxt: 9.0x00000658
enxt: 8.0x00000228 enxt: 7.0x00000fd8 enxt: 6.0x00000fa0 enxt: 5.0x00000248
enxt: 4.0x00000fa0 enxt: 3.0x00000410 enxt: 2.0x00000480 enxt: 1.0x00000f70
pnxt: 1.0x00000030
kxscphp=0x7f5227960c70 siz=2792 inu=1056 nps=424
kxscbhp=0x7f5227960e50 siz=10376 inu=10008 nps=8768
Cursor frame dump
enxt: 3.0x00000550 enxt: 2.0x00000040 enxt: 1.0x000007a0
pnxt: 1.0x00000030
kxscphp=0x7f5227961030 siz=984 inu=584 nps=360
kxscbhp=0x7f5227961920 siz=984 inu=152 nps=0
kxscwhp=0x7f5227960f40 siz=4056 inu=56 nps=0
Cursor#1游標(biāo)部分：
Cursor frame dump
enxt: 12.0x000005c0 enxt: 11.0x00000fd8 enxt: 10.0x00000fa0 enxt: 9.0x00000658
enxt: 8.0x00000228 enxt: 7.0x00000fd8 enxt: 6.0x00000fa0 enxt: 5.0x00000248
enxt: 4.0x00000fa0 enxt: 3.0x00000410 enxt: 2.0x00000480 enxt: 1.0x00000f70
pnxt: 1.0x00000030
kxscphp=0x7f5227960c70 siz=2792 inu=1056 nps=424
kxscbhp=0x7f5227960e50 siz=10376 inu=10008 nps=8768
在cursor frame dump部分我們可以看見kxsc開始的一些信息，這些意味著Kernel eXECUTION Shared Cursor，其中的每一行的siz參數(shù)告訴我們當(dāng)前分配的私有內(nèi)存大小。當(dāng)然，我們需要匯總所有的siz，這個(gè)值就是此游標(biāo)的memory usage。
下面是我的一些猜測(cè)匯總：
01.Heap description Meaning
02.kxscphp Cursor permanent heap. Allocated when cursor is opened
03.kxscdfhp Cursor default heap - default duration allocations
04.kxscehp Cursor ephemeral heap - short lived duration allocations
05.kxscwhp Cursor Work heap - used when actually executing the cursor (workareas etc)
06.kxscbhp Cursor Bind heap - this is where bind variable values and their metadata are kept.
四、實(shí)驗(yàn)代碼
1、創(chuàng)建表和PL/SQL函數(shù)
create table dh_t (id number(2,1),name varchar2(200));
create or replace procedure p_dh1 as
v_id number :=1234335;
v_name varchar2(200) :='oradh';
begin
--just for errorstack test
insert into dh_t values (v_id,v_name);
commit;
end;
/
create or replace procedure p_dh2 as
v_cnt number;
begin
----just for errorstack test
select count(*) into v_cnt from dh_t;
dbms_output.put_line('the dh_t count is '||v_cnt);
p_dh1;
end;
/
create or replace procedure p_dh1 as
v_id number :=1234335;
v_name varchar2(200) :='oradh';
begin
--just for errorstack test
insert into dh_t values (v_id,v_name);
commit;
end;
/
create or replace procedure p_dh2 as
v_cnt number;
begin
----just for errorstack test
select count(*) into v_cnt from dh_t;
dbms_output.put_line('the dh_t count is '||v_cnt);
p_dh1;
end;
/
2、進(jìn)行errorstack跟蹤
SQL*Plus: Release 11.2.0.1.0 Production on Tue Jul 1 11:15:52 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
SQL> set linesize 200 pagesize 999
SQL> col tracefile format a100
SQL> select spid,tracefile from v$process a where addr=(select paddr from v$session where sid=(select sid from v$mystat where rownum=1));
SPID TRACEFILE
--------------- --------------------------------------------------------------------------------------------------
10848 /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
SQL> alter session set events='1438 trace name errorstack forever,level 3';
Session altered.
SQL> exec p_dh2;
BEGIN p_dh2; END;
*
ERROR at line 1:
ORA-01438: value larger than specified precision allowed for this column
ORA-06512: at "DBMON.P_DH1", line 6
ORA-06512: at "DBMON.P_DH2", line 7
ORA-06512: at line 1
[oracle@192oracle ~]$ ls -ltr /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
-rw-r----- 1 oracle oinstall 12190347 Jul 1 11:16 /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
SQL> set linesize 200 pagesize 999
SQL> col tracefile format a100
SQL> select spid,tracefile from v$process a where addr=(select paddr from v$session where sid=(select sid from v$mystat where rownum=1));
SPID TRACEFILE
--------------- --------------------------------------------------------------------------------------------------
10848 /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
SQL> alter session set events='1438 trace name errorstack forever,level 3';
Session altered.
SQL> exec p_dh2;
BEGIN p_dh2; END;
*
ERROR at line 1:
ORA-01438: value larger than specified precision allowed for this column
ORA-06512: at "DBMON.P_DH1", line 6
ORA-06512: at "DBMON.P_DH2", line 7
ORA-06512: at line 1
[oracle@192oracle ~]$ ls -ltr /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
-rw-r----- 1 oracle oinstall 12190347 Jul 1 11:16 /u01/oracle/diag/rdbms/cn100/cn100/trace/cn100_ora_10848.trc
