1 oradebug介绍
oradebug主要是给oracle支持人员使用的,尽管很早便有,但oracle官网很少有记载。他是个sql*plus命令行工具,有sysdba的权限就可以登入,无需特别设置。他可以被用于:
1)追踪进程,或者是你的,或者是外部的
2)确定进程往哪个trc文件写
3)转储:数据文件头、内部oracle结构等
4)挂起进程,暂时的
5)确定实例使用了哪些共享内存块和信号量
6)找出RAC实例使用了哪些互联地址和协议
7)修改SGA中的数据结构
2 oradebug使用步骤
1)启动sql*plus并以sysdba身份登入
2)连接到一个进程
3)设置一个事件或者进行诊断转储
4)检索trc文件名
5)与连接到的进程断开
3 oradebug命令介绍
- sys@ORCL> oradebug help
- HELP [command] Describe one or all commands
- SETMYPID Debug current process
- SETOSPID <ospid> Set OS pid of process to debug
- SETORAPID <orapid> ['force'] Set Oracle pid of process to debug
- SHORT_STACK Dump abridged OS stack
- DUMP <dump_name> <lvl> [addr] Invoke named dump
- DUMPSGA [bytes] Dump fixed SGA
- DUMPLIST Print a list of available dumps
- EVENT <text> Set trace event in process
- SESSION_EVENT <text> Set trace event in session
- DUMPVAR <p|s|uga> <name> [level] Print/dump a fixed PGA/SGA/UGA variable
- DUMPTYPE <address> <type> <count> Print/dump an address with type info
- SETVAR <p|s|uga> <name> <value> Modify a fixed PGA/SGA/UGA variable
- PEEK <addr> <len> [level] Print/Dump memory
- POKE <addr> <len> <value> Modify memory
- WAKEUP <orapid> Wake up Oracle process
- SUSPEND Suspend execution
- RESUME Resume execution
- FLUSH Flush pending writes to trace file
- CLOSE_TRACE Close trace file
- TRACEFILE_NAME Get name of trace file
- LKDEBUG Invoke global enqueue service debugger
- NSDBX Invoke CGS name-service debugger
- -G <Inst-List | def | all> Parallel oradebug command prefix
- -R <Inst-List | def | all> Parallel oradebug prefix (return output
- SETINST <instance# .. | all> Set instance list in double quotes
- SGATOFILE <SGA dump dir> Dump SGA to file; dirname in double quotes
- DMPCOWSGA <SGA dump dir> Dump & map SGA as COW; dirname in double quotes
- MAPCOWSGA <SGA dump dir> Map SGA as COW; dirname in double quotes
- HANGANALYZE [level] [syslevel] Analyze system hang
- FFBEGIN Flash Freeze the Instance
- FFDEREGISTER FF deregister instance from cluster
- FFTERMINST Call exit and terminate instance
- FFRESUMEINST Resume the flash frozen instance
- FFSTATUS Flash freeze status of instance
- SKDSTTPCS <ifname> <ofname> Helps translate PCs to names
- WATCH <address> <len> <self|exist|all|target> Watch a region of memory
- DELETE <local|global|target> watchpoint <id> Delete a watchpoint
- SHOW <local|global|target> watchpoints Show watchpoints
- CORE Dump core without crashing process
- IPC Dump ipc information
- UNLIMIT Unlimit the size of the trace file
- PROCSTAT Dump process statistics
- CALL <func> [arg1] ... [argn] Invoke function with arguments
4 连接到一个进程
在oradebug命令执行之前,你必须加入一个目标进程。这个目标进程有如下3种情况:
命令 |
目的 |
oradebug setmypid |
连接到为你的sql*plus提供服务的进程 |
oradebug setorapid pid |
连接到一个外部服务进程,且pid=v$process.pid |
oradebug setospid spid |
连接到一个外部服务进程,且spid=v$process.pid |
1) setmypid
- sys@ORCL> oradebug setmypid
- Statement processed.
- sys@ORCL> oradebug unlimit
- Statement processed.
- sys@ORCL> oradebug event 10046 trace name context forever,level 8
- Statement processed.
- sys@ORCL> select * from hr.departments where department_id=10;
- DEPARTMENT_ID DEPARTMENT_NAME MANAGER_ID LOCATION_ID
- ------------- ------------------------------ ---------- -----------
- 10 Administration 200 1700
- sys@ORCL> oradebug tracefile_name
- /u01/app/oracle/admin/orcl/udump/orcl_ora_5234.trc
- sys@ORCL> oradebug event 10046 trace name context off
- Statement processed.
2)setospid(spid操作)
- sys@ORCL> host top
- top - 15:14:20 up 47 min, 2 users, load average: 0.22, 0.20, 0.26
- Tasks: 171 total, 2 running, 168 sleeping, 0 stopped, 1 zombie
- Cpu(s): 1.3%us, 1.3%sy, 0.0%ni, 97.4%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
- Mem: 678912k total, 671192k used, 7720k free, 16672k buffers
- Swap: 0k total, 0k used, 0k free, 401584k cached
- PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
- 5874 oracle 15 0 2444 1084 828 R 1.6 0.2 0:00.47 top
- 4781 root 15 0 53900 11m 6076 S 0.7 1.7 1:00.13 Xorg
- 5168 oracle 16 0 491m 17m 15m S 0.3 2.6 0:02.41 oracle
- sys@ORCL> oradebug setospid 5168
- Oracle pid: 7, Unix process pid: 5168, image: oracle@localhost.localdomain (CKPT)
3)setorapid(pid操作)
- sys@ORCL> select sid from v$mystat where rownum=1;
- SID
- ----------
- 159
- sys@ORCL> select pid,spid from v$process p,v$session s where s.sid=159 and s.paddr=p.addr;
- PID SPID
- ---------- ------------
- 15 5234
- sys@ORCL> oradebug setorapid 15
- Statement processed.
- sys@ORCL> oradebug tracefile_name
- /u01/app/oracle/admin/orcl/udump/orcl_ora_5234.trc
- sys@ORCL> oradebug event 10046 trace name context off
- Statement processed.
注意,在OEM的top session也可以等价实现上述效果,即:确定哪些数据库会话消耗了较多的资源
5 oradebug IPC
查看共享信息的内存的命令是ipcs [-m|-s|-q]。默认会列出共享内存、信号量,队列信息,-m列出共享内存,-s列出共享信号量,-q列出共享队列
- sys@ORCL> host ipcs -m | grep ora
- 0xbe3bb918 5439503 oracle 640 419438592 20
- sys@ORCL> oradebug setmypid
- Statement processed.
- sys@ORCL> oradebug ipc
- Information written to trace file.
- sys@ORCL> oradebug tracefile_name
- /u01/app/oracle/admin/orcl/udump/orcl_ora_5234.trc
- sys@ORCL> oradebug event 10046 trace name context off
- Statement processed.
当一台电脑的资源有限时,失败的实例占用共享内存和信号量会导致资源紧张,从而使得新的oracle实例无法启动。
清除命令是ipcrm [-m|-s|-q] id。
-m 删除共享内存,-s删除共享信号量,-q删除共享队列
如:ipcrm -m 5439503
6 oradebug SHORT_STACK
如果一个程序挂起,那么程序调用栈就可以显示它在调用路径中的哪一步挂起
- sys@ORCL> oradebug setospid 5180
- Oracle pid: 13, Unix process pid: 5180, image: oracle@localhost.localdomain (D000)
- sys@ORCL> oradebug short_stack
- ksdxfstk()+19<-ksdxcb()+1321<-sspuser()+81<-__kernel_vsyscall()+2<-ntevpque()+112<-ntevque()+606<-nsevwait()+821<-ksnwait()+111<-ksliwat()+770<-kslwaitns()+29<-
- kskthbwt()+370<-kslwait()+57<-kmdmai()+1797<-kmmrdp()+432<-opirip()+1191<-opidrv()+864<-sou2o()+113<-opimai_real()+353<-main()+111<-__libc_start_main()+220
- sys@ORCL> oradebug event 10046 trace name context off
- Statement processed.
当前的调用步骤在输出的顶部
7 诊断转储
可转储类型如下:
- sys@ORCL> oradebug dumplist
- EVENTS
- TRACE_BUFFER_ON
- TRACE_BUFFER_OFF
- HANGANALYZE
- LATCHES
- PROCESSSTATE
- SYSTEMSTATE
- INSTANTIATIONSTATE
- .........
下面举例两个:
1)controlf
- sys@ORCL> oradebug setmypid
- Statement processed.
- sys@ORCL> oradebug dump controlf 10
- Statement processed.
- sys@ORCL> oradebug tracefile_name
- /u01/app/oracle/admin/orcl/udump/orcl_ora_5234.trc
2)events
这不是真正的转储,events只是将激活的事件写入trc文件。如果你不能确定一个会话、进程或者实例中哪个事件是活动的,下面有一种很好的方式去查询:
- sys@ORCL> alter session set events '10046 trace name context forever,level 8';
- Session altered.
- sys@ORCL> alter session set events '4031 trace name heapdump level 3';
- Session altered.
- sys@ORCL> oradebug setmypid
- Statement processed.
- sys@ORCL> oradebug dump events 1
- Statement processed.
- sys@ORCL> oradebug tracefile_name
- /u01/app/oracle/admin/orcl/udump/orcl_ora_5234.trc
- sys@ORCL> oradebug event 10046 trace name context off
- Statement processed.
oradebug dump events的级别和范围
级别 | 事件范围 | 使用的命令 |
1 | 会话 | alter session |
2 | 进程 | oradebug event |
4 | 实例 | alter system |
8 小结
oradebug对于解决问题和诊断性能是必不可少的工具。本文只是讲述了一些最常见的命令,还有更多的功能,比如RAC环境下调用全局队列服务调试器的
oradebug lkdebug命令。