使用堆栈跟踪

在某些操作系统上，如果mysqld意外死亡，则错误日志包含堆栈跟踪。您可以使用它来找出mysqld死于何处（也许是为什么）。请参见“MySQL服务器错误日志”。为了获得堆栈跟踪，必须不要编译带有 gcc选项的mysqld-fomit-frame-pointer。请参见 29.5.1.1，“编译MySQL以进行调试”。

错误日志中的堆栈跟踪如下所示：

mysqld got signal 11;
Attempting backtrace. You can use the following information
to find out where mysqld died. If you see no messages after
this, something went terribly wrong...

stack_bottom = 0x41fd0110 thread_stack 0x40000
mysqld(my_print_stacktrace+0x32)[0x9da402]
mysqld(handle_segfault+0x28a)[0x6648e9]
/lib/libpthread.so.0[0x7f1a5af000f0]
/lib/libc.so.6(strcmp+0x2)[0x7f1a5a10f0f2]
mysqld(_Z21check_change_passwordP3THDPKcS2_Pcj+0x7c)[0x7412cb]
mysqld(_ZN16set_var_password5checkEP3THD+0xd0)[0x688354]
mysqld(_Z17sql_set_variablesP3THDP4ListI12set_var_baseE+0x68)[0x688494]
mysqld(_Z21mysql_execute_commandP3THD+0x41a0)[0x67a170]
mysqld(_Z11mysql_parseP3THDPKcjPS2_+0x282)[0x67f0ad]
mysqld(_Z16dispatch_command19enum_server_commandP3THDPcj+0xbb7[0x67fdf8]
mysqld(_Z10do_commandP3THD+0x24d)[0x6811b6]
mysqld(handle_one_connection+0x11c)[0x66e05e]

如果跟踪的函数名称解析失败，则跟踪将包含较少的信息：

mysqld got signal 11;
Attempting backtrace. You can use the following information
to find out where mysqld died. If you see no messages after
this, something went terribly wrong...

stack_bottom = 0x41fd0110 thread_stack 0x40000
[0x9da402]
[0x6648e9]
[0x7f1a5af000f0]
[0x7f1a5a10f0f2]
[0x7412cb]
[0x688354]
[0x688494]
[0x67a170]
[0x67f0ad]
[0x67fdf8]
[0x6811b6]
[0x66e05e]

较新版本的glibc堆栈跟踪功能还会打印相对于对象的地址。在glibc基于系统的系统（Linux）上，插件内崩溃的跟踪类似于：

plugin/auth/auth_test_plugin.so(+0x9a6)[0x7ff4d11c29a6]

要将相对地址（+0x9a6）转换为文件名和行号，请使用以下命令：

shell>addr2line -fie auth_test_plugin.so 0x9a6
auth_test_plugin
mysql-trunk/plugin/auth/test_plugin.c:65

该addr2line实用程序是部分binutils包在Linux上。

在Solaris上，过程类似。Solaris printstack()已经打印了相对地址：

plugin/auth/auth_test_plugin.so:0x1510

要翻译，请使用以下命令：

shell>gaddr2line -fie auth_test_plugin.so 0x1510
mysql-trunk/plugin/auth/test_plugin.c:88

Windows已经打印了地址，函数名称和行：

000007FEF07E10A4 auth_test_plugin.dll!auth_test_plugin()[test_plugin.c:72]