If the mysqld server doesn't start or if you can cause it to crash quickly, you can try to create a trace file to find the problem.
To do this, you must have a mysqld that has
been compiled with debugging support. You can check this by
executing mysqld -V
. If the version number
ends with -debug
, it is compiled with
support for trace files. (On Windows, the debugging server is
named mysqld-debug rather than
mysqld as of MySQL 4.1.)
Start the mysqld server with a trace log in
/tmp/mysqld.trace
on Unix or
C:\mysqld.trace
on Windows:
shell> mysqld --debug
On Windows, you should also use the
--standalone
flag to not start
mysqld as a service. In a console window,
use this command:
C:\> mysqld-debug --debug --standalone
After this, you can use the mysql.exe
command-line tool in a second console window to reproduce the
problem. You can stop the mysqld server
with mysqladmin shutdown.
Note that the trace file become very big! If you want to generate a smaller trace file, you can use debugging options something like this:
mysqld --debug=d,info,error,query,general,where:O,/tmp/mysqld.trace
This only prints information with the most interesting tags to the trace file.
If you make a bug report about this, please only send the lines from the trace file to the appropriate mailing list where something seems to go wrong! If you can't locate the wrong place, you can ftp the trace file, together with a full bug report, to ftp://ftp.mysql.com/pub/mysql/upload/ so that a MySQL developer can take a look at it.
The trace file is made with the DBUG package by Fred Fish. See Section 22.5.3, “The DBUG Package”.
User Comments
User Guide explaining how to collect DBUG Traces: http://blogs.sun.com/amitsaha/entry/obtaining_mysql_server_execution_traces
Add your own comment.