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(mysql.info)Making trace files

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Creating trace files
--------------------

If the `mysqld' server doesn't start or if you can cause the `mysqld'
server to crash quickly, you can try to create a trace file to find the
problem.

To do this you have to have a `mysqld' that is compiled for debugging.
You can check this by executing `mysqld -V'.  If the version number
ends with `-debug', it's compiled with support for trace files.

Start the `mysqld' server with a trace log in `/tmp/mysqld.trace' (or
`C:\mysqld.trace' on Windows):

`mysqld --debug'

On Windows you should also use the `--standalone' flag to not start
`mysqld' as a service:

In a DOS window do:

     mysqld --debug --standalone

After this you can use the `mysql.exe' command line tool in a second
DOS window to reproduce the problem. You can take down the above
`mysqld' server with `mysqladmin shutdown'.

Note that the trace file will get very _BIG_!  If you want to have a
smaller trace file, you can use something like:

`mysqld --debug=d,info,error,query,general,where:O,/tmp/mysqld.trace'

which only prints information with the most interesting tags in
`/tmp/mysqld.trace'.

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://support.mysql.com/pub/mysql/secret' so that a MySQL developer
can take a look a this.

The trace file is made with the *DBUG* package by Fred Fish.  Note: The
DBUG package.