用vimgdb调试c++时候，当调试到cin语句要求输入时，gdb就卡在那里等待输入，请问这个问题有解决办法吗？谢

发布网友 发布时间：2022-04-11 23:45

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共2个回答

懂视网 时间：2022-04-12 04:07

转载请注明出处：http://blog.csdn.net/guoyjoe/article/details/18461845 发生read by other session 等待事件，肯定是两个会话同时物理读同一个数据块，假设有两个会话，会话1发生物理读，会话2正要去物理读发现会话1正在物读理产生，此时会话2发生等待，

转载请注明出处：http://blog.csdn.net/guoyjoe/article/details/18461845

发生read by other session 等待事件，肯定是两个会话同时物理读同一个数据块，假设有两个会话，会话1发生物理读，会话2正要去物理读发现会话1正在物读理产生，此时会话2发生等待，此等待就是read by other session 等待事件。

实验步骤如下：

gyj@OCM> select spid from v$session s,v$process p where s.paddr=p.addr and sid in(select distinct sid from v$mystat);

SPID
------------------------
7376

2、刷新buffer cache,目的就是让select发生物理读

gyj@OCM> alter system flush buffer_cache;

System altered.

3、通过进程号7376,打开gdb

[oracle@mydb ~]$ gdb $ORACLE_HOME/bin/oracle 7376
GNU gdb Fedora (6.8-27.el5)
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu"...
(no debugging symbols found)
Attaching to program: /u01/app/oracle/product/11.2.0/bin/oracle, process 7376
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libodm11.so...(no debugging symbols found)...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libodm11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libcell11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libcell11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libskgxp11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libskgxp11.so
Reading symbols from /lib64/librt.so.1...done.
Loaded symbols for /lib64/librt.so.1
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libnnz11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libnnz11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libclsra11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libclsra11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libdbcfg11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libdbcfg11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libhasgen11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libhasgen11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libskgxn2.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libskgxn2.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libocr11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libocr11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libocrb11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libocrb11.so
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libocrutl11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libocrutl11.so
Reading symbols from /usr/lib64/libaio.so.1...done.
Loaded symbols for /usr/lib64/libaio.so.1
Reading symbols from /lib64/libdl.so.2...done.
Loaded symbols for /lib64/libdl.so.2
Reading symbols from /lib64/libm.so.6...done.
Loaded symbols for /lib64/libm.so.6
Reading symbols from /lib64/libpthread.so.0...done.
[Thread debugging using libthread_db enabled]
[New Thread 0x2b0b8fef0910 (LWP 7376)]
Loaded symbols for /lib64/libpthread.so.0
Reading symbols from /lib64/libnsl.so.1...done.
Loaded symbols for /lib64/libnsl.so.1
Reading symbols from /lib64/libc.so.6...done.
Loaded symbols for /lib64/libc.so.6
Reading symbols from /lib64/ld-linux-x86-64.so.2...done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2
Reading symbols from /usr/lib64/libnuma.so.1...done.
Loaded symbols for /usr/lib64/libnuma.so.1
Reading symbols from /lib64/libnss_files.so.2...done.
Loaded symbols for /lib64/libnss_files.so.2
Reading symbols from /u01/app/oracle/product/11.2.0/lib/libnque11.so...done.
Loaded symbols for /u01/app/oracle/product/11.2.0/lib/libnque11.so
0x0000003f0d40d290 in __read_nocancel () from /lib64/libpthread.so.0
(gdb) 

4、在会话1，执行select语句，此时select被阻塞

gyj@OCM> select * from gyj_test where id=1;

5、在gdb设断点，用等待事件的函数，并运行

(gdb) b kslwtbctx
Breakpoint 1 at 0x8f9a5c2
(gdb) c
Continuing.

(gdb) info all-register
rax  0x62657100 1650815232
rbx  0x15c 348
rcx  0x0 0
rdx  0x1 1
rsi  0x7a59 31321
rdi  0x7fff1c576d40 140733668879680
rbp  0x7fff1c576ce0 0x7fff1c576ce0
rsp  0x7fff1c576ce0 0x7fff1c576ce0
r8  0x2 2
r9  0x25 37
r10  0x7 7
r11  0x0 0
r12  0x0 0
r13  0xbb0c348 196133704
r14  0xbb09d40 196123968
r15  0x1 1
rip  0x8f9a5c2 0x8f9a5c2 
eflags  0x246 [ PF ZF IF ]
cs  0x33 51
ss  0x2b 43
ds  0x0 0
es  0x0 0
fs  0x0 0
gs  0x0 0
st0  0 (raw 0x00000000000000000000)
---Type  to continue, or q  to quit---
st1  0 (raw 0x00000000000000000000)
st2  0 (raw 0x00000000000000000000)
st3  0 (raw 0x00000000000000000000)
st4  0 (raw 0x00000000000000000000)
st5  0 (raw 0x00000000000000000000)
st6  73280 (raw 0x400f8f20000000000000)
st7  73280 (raw 0x400f8f20000000000000)
fctrl  0x27f 639
fstat  0x0 0
ftag  0xffff 65535
fiseg  0x0 0
fioff  0x9394e95 154750613
foseg  0x7fff 32767
fooff  0x1c573f50 475479888
fop  0x0 0

8、用x/32命令查内存中32个字节

gdb) x/32 0x7fff1c576d40
0x7fff1c576d40: 0x1c577a59 0x00007fff 0x1c576e50 0x00007fff
0x7fff1c576d50: 0x1c576ee0 0x00007fff 0x0918adf2 0x00000000
0x7fff1c576d60: 0x00000000 0x00000000 0x00000000 0x00000000
0x7fff1c576d70: 0x00000000 0x00000001 0x00000000 0x00000000
0x7fff1c576d80: 0x002adb17 0x00000000 0x00000000 0x00000000
0x7fff1c576d90: 0x00000000 0x00000000 0x00000001 0x00000000
0x7fff1c576da0: 0x09b958cc 0x00000000 0x0000015c 0x00000000
0x7fff1c576db0: 0x7fffffff 0x00000000 0x62657100 0x00000000

9、找到0x0000015c，通过此等待事件号，找等待事件

gyj@OCM> select name from v$event_name where event# in(select to_number('15c','xxxxxxxxxxxxxx') from dual);


NAME
----------------------------------------------------------------
SQL*Net message to client

10、重复第5、6、7、8、9步(注用从第5步的c命令开始）

(gdb) c
Continuing.

Breakpoint 1, 0x0000000008f9a5c2 in kslwtbctx ()
(gdb) info all-register
rax  0x0 0
rbx  0x2000 8192
rcx  0x0 0
rdx  0x0 0
rsi  0x0 0
rdi  0x7fff1c574c38 140733668871224
rbp  0x7fff1c574970 0x7fff1c574970
rsp  0x7fff1c574970 0x7fff1c574970
r8  0x5bbb295 96187029
r9  0x2f8b5f0 49853936
r10  0x52da848e 1390052494
r11  0x2b0b9057e7a8 47328666314664
r12  0x99837da8 2575531432
r13  0x0 0
r14  0x0 0
r15  0x99437498 2571334808
rip  0x8f9a5c2 0x8f9a5c2 
eflags  0x246 [ PF ZF IF ]
cs  0x33 51
ss  0x2b 43
ds  0x0 0
es  0x0 0
fs  0x0 0
gs  0x0 0
st0  0 (raw 0x00000000000000000000)
---Type  to continue, or q  to quit---
st1  0 (raw 0x00000000000000000000)
st2  0 (raw 0x00000000000000000000)
st3  0 (raw 0x00000000000000000000)
st4  0 (raw 0x00000000000000000000)
st5  0 (raw 0x00000000000000000000)
st6  73280 (raw 0x400f8f20000000000000)
st7  73280 (raw 0x400f8f20000000000000)
fctrl  0x27f 639
fstat  0x0 0
ftag  0xffff 65535
fiseg  0x0 0
fioff  0x9394e95 154750613
foseg  0x7fff 32767
fooff  0x1c573f50 475479888
fop  0x0 0
xmm0  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm1  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm2  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm3  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0, 0x0, 0x0, 0x0, 0x54, 0x3, 0x1, 0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0, 0x0}, v8_int16 = {0x0, 0x0, 0x354, 0x1, 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x10354, 0x0, 0x0}, v2_int64 = {
 0x1035400000000, 0x0}, uint128 = 0x00000000000000000001035400000000}
xmm4  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x64, 0x0 }, v8_int16 = {0x64, 0x0, 
---Type  to continue, or q  to quit---
 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x64, 0x0, 0x0, 0x0}, v2_int64 = {0x64, 0x0}, uint128 = 0x00000000000000000000000000000064}
xmm5  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x32, 0xa3, 0xd7, 0x2, 0x0 }, 
 v8_int16 = {0xa332, 0x2d7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x2d7a332, 0x0, 0x0, 0x0}, v2_int64 = {0x2d7a332, 0x0}, 
 uint128 = 0x00000000000000000000000002d7a332}
xmm6  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm7  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0xda, 0x87, 0xd7, 0x2, 0x0 }, 
 v8_int16 = {0x87da, 0x2d7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x2d787da, 0x0, 0x0, 0x0}, v2_int64 = {0x2d787da, 0x0}, 
 uint128 = 0x00000000000000000000000002d787da}
xmm8  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm9  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm10  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm11  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm12  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x18, 0xe, 0x73, 0x90, 0xb, 0x2b, 0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, v8_int16 = {0xe18, 0x9073, 0x2b0b, 0x0, 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x90730e18, 0x2b0b, 0x0, 0x0}, 
 v2_int64 = {0x2b0b90730e18, 0x0}, uint128 = 0x000000000000000000002b0b90730e18}
xmm13  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm14  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
xmm15  {v4_float = {0x0, 0x0, 0x0, 0x0}, v2_double = {0x0, 0x0}, v16_int8 = {0x0 }, v8_int16 = {0x0, 0x0, 0x0, 0x0, 
---Type  to continue, or q  to quit---
 0x0, 0x0, 0x0, 0x0}, v4_int32 = {0x0, 0x0, 0x0, 0x0}, v2_int64 = {0x0, 0x0}, uint128 = 0x00000000000000000000000000000000}
mxcsr  0x1fa1 [ IE PE IM DM ZM OM UM PM ]
(gdb) 
(gdb) x/32 0x7fff1c574c38
0x7fff1c574c38: 0x08f97a59 0x00000000 0x9079c6d8 0x00002b0b
0x7fff1c574c48: 0x90742970 0x00002b0b 0x9079c748 0x00002b0b
0x7fff1c574c58: 0x1c574df0 0x00007fff 0x9079c748 0x00002b0b
0x7fff1c574c68: 0x9079c6d8 0x00002b0b 0x00000000 0x00000000
0x7fff1c574c78: 0x00000000 0x00000000 0x00000013 0x20000000
0x7fff1c574c88: 0x00000000 0x00000000 0x00000001 0x00000000
0x7fff1c574c98: 0x0a0fcd50 0x00000000 0x00000092 0x00000000
0x7fff1c574ca8: 0x7fffffff 0x00000000 0x00000006 0x00000000
(gdb) 

gyj@OCM> gyj@OCM> select name from v$event_name where event# in(select to_number('92','xxxxxxxxxxxxxx') from dual);

NAME
----------------------------------------------------------------
db file sequential read

gyj@OCM> select sid from v$mystat where rownum=1;

 SID
----------
 146

 gyj@OCM> select * from gyj_test where id=1;

sys@OCM> select sid ,event from v$session_wait where sid=146 and wait_class<>'Idle';

 SID EVENT
---------- ----------------------------------------------------------------
 146 read by other session

热心网友 时间：2022-04-12 01:15

追答没用过，不用vim很久了。。