gdb调试之--read by other session 等待事件的重现
2014-01-21 20:02
519 查看
gdb调试之--read by other session 等待事件的重现
分类：Oracle Debug2014-01-18 21:55290人阅读评论(0)收藏举报
转载请注明出处：/article/1630134.html
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：
1、开会话1，先查出会话1的进程号7376
[html]
view plaincopyprint?
gyj@OCM> select spid from v$session s,v$process p where
s.paddr=p.addr and sid in(select distinct sid from v$mystat);
SPID
------------------------
7376
gyj@OCM> select spid from v$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
[html]
view plaincopyprint?
gyj@OCM> alter system flush buffer_cache; System altered.
gyj@OCM> alter system flush buffer_cache; System altered.
3、通过进程号7376,打开gdb
[html]
view plaincopyprint?
[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 <http://gnu.org/licenses/gpl.html>
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)
[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 <http://gnu.org/licenses/gpl.html> 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
[html]
view plaincopyprint?
gyj@OCM> select * from gyj_test where
id=1;
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
[html]
view plaincopyprint?
(gdb) b kslwtbctx Breakpoint 1 at 0x8f9a5c2 (gdb) c Continuing.
(gdb) b kslwtbctx Breakpoint 1 at 0x8f9a5c2 (gdb) c Continuing.
6、查等待事件kslwtbctx函数的第一个参数，用命令info all-register显示寄存器
[html]
view plaincopyprint?
(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 <kslwtbctx+4>
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 <return> to continue, or q
<return> 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
(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 <kslwtbctx+4> 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 <return> to continue, or q <return> 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
7、找到第一个参数
rdi 0x7fff1c576d40
8、用x/32命令查内存中32个字节
[html]
view plaincopyprint?
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
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
[html]
view plaincopyprint?
gyj@OCM> select name from v$event_name where event# in(select to_number('15c','xxxxxxxxxxxxxx') from dual);
NAME
----------------------------------------------------------------
SQL*Net message to client
gyj@OCM> select name from v$event_name where event# in(select to_number('15c','xxxxxxxxxxxxxx') from dual);
NAME
----------------------------------------------------------------
SQL*Net message to client10、重复第5、6、7、8、9步(注用从第5步的c命令开始）
[html]
view plaincopyprint?
(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 <kslwtbctx+4>
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 <return> to continue, or q
<return> 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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 15 times>},
v8_int16 = {0x64, 0x0,
---Type <return> to continue, or q
<return> 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
<repeats 12 times>},
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
<repeats 16 times>},
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
<repeats 12 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
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
<repeats 16 times>},
v8_int16 = {0x0, 0x0, 0x0, 0x0,
---Type <return> to continue, or q
<return> 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)
(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 <kslwtbctx+4>
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 <return> to continue, or q <return> 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 15 times>}, v8_int16 = {0x64, 0x0,
---Type <return> to continue, or q <return> 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 <repeats 12 times>},
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 <repeats 16 times>}, 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 <repeats 12 times>},
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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, 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 <repeats 16 times>}, v8_int16 = {0x0, 0x0, 0x0, 0x0,
---Type <return> to continue, or q <return> 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)11、找到0x00000092，通过此等待事件号，找等待事件0x00000092
[html]
view plaincopyprint?
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> gyj@OCM> select name from v$event_name where event# in(select to_number('92','xxxxxxxxxxxxxx') from dual);
NAME
----------------------------------------------------------------
db file sequential read说明此时会话1发生了物理读（db file sequential read等待事件你懂我）
12、打开会话2（此会话2号的SID=146）,并在会话2执行SELECT语句，此时SELECT也被阻塞了
[html]
view plaincopyprint?
gyj@OCM> select sid from v$mystat where
rownum=1;
SID
----------
146
gyj@OCM> select * from gyj_test where
id=1;
gyj@OCM> select sid from v$mystat where rownum=1; SID ---------- 146 gyj@OCM> select * from gyj_test where id=1;
13、打开一个会话3，看会话2（此会话2号的SID=146）的等待事件
[html]
view plaincopyprint?
sys@OCM> select sid ,event from v$session_wait where
sid=146 and wait_class<>'Idle';
SID EVENT
---------- ----------------------------------------------------------------
146 read by other session
sys@OCM> select sid ,event from v$session_wait where sid=146 and wait_class<>'Idle'; SID EVENT ---------- ---------------------------------------------------------------- 146 read by other session
哈哈。。。终于发现了read by other session等待事件，以后可以用同样的方法去研究其它等待事件！
QQ：252803295
技术交流QQ群：
DSI&Core Search Ⅰ 群：127149411（2000人技术群:未满）
DSI&Core Search Ⅱ 群：177089463（1000人技术群:未满）
DSI&Core Search Ⅲ 群：284596437（500人技术群:未满）
DSI&Core Search Ⅳ 群：192136702（500人技术群:未满）
DSI&Core Search Ⅴ 群：285030382（500人闲聊群:未满）
MAIL：dbathink@hotmail.com
BLOG： http://blog.csdn.net/guoyjoe
WEIBO：http://weibo.com/guoyJoe0218
ITPUB： http://www.itpub.net/space-uid-28460966.html
OCM： http://education.oracle.com/education/otn/YGuo.HTM
ACONG: http://www.acoug.org/category/membership
更多0
上一篇：gdb调试之---当commit时碰到的第一个等待事件是什么？
下一篇：计算SGA各池的内存地址的边界
内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理 
相关文章推荐
- gdb调试之--read by other session 等待事件的重现
- gdb调试之--read by other session 等待事件的重现
- read by other session等待事件
- read by other session等待事件
- read by other session等待事件
- read by other session 等待事件。
- 系统遇到read by other session等待事件
- 等待事件：read by other session
- 等待事件read by other session
- read by other session 等待事件处理
- read by other session等待事件
- read by other session 等待事件。
- “read by other session”等待事件引发的数据库性能问题
- read by other session等待事件
- Read by other session 等待说明
- Oracle 10g read by other session 等待 说明
- Oracle 10g read by other session 等待 说明
- Oracle 10g read by other session 等待 说明
- AWR实战分析之---- read by other session
- Select/Update 引起的read by other session