Bug #51739 --core-file is not default TRUE (incorrect docs)
Submitted: 4 Mar 2010 21:55 Modified: 5 Mar 2010 16:46
Reporter: Ronald Bradford Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:5.1.38 OS:Linux
Assigned to: Paul Dubois CPU Architecture:Any
Tags: --core-file, Docs, mysqld
Triage: Needs Triage: D2 (Serious)

[4 Mar 2010 21:55] Ronald Bradford
Description:
The documentation at http://dev.mysql.com/doc/refman/5.1/en/server-options.html#option_mysqld_core-file  states that the default for --core-file is TRUE, however testing and confirmation by support on #mysql-dev indicates otherwise.

How to repeat:
$ bin/mysqld_safe ...

$ ps -ef | grep "5.1.38"
rbradfor  2232  3253  0 16:46 pts/3    00:00:00 /home/rbradfor/mysql/mysql-5.1.38-linux-x86_64-glibc23/bin/mysqld --defaults-file=./my.cnf ...
rbradfor  2331  1314  0 16:46 pts/3    00:00:00 grep 5.1.38

$ kill -11 2232
100304 16:46:57 mysqld_safe Number of processes running now: 0
100304 16:46:57 mysqld_safe mysqld restarted

Add to my.cnf

[mysqld]
core-file

$ ps -ef | grep "5.1.38"
rbradfor  2110  1314  0 16:46 pts/3    00:00:00 grep 5.1.38
rbradfor  2656  3253  0 16:33 pts/3    00:00:00 /home/rbradfor/mysql/mysql-5.1.38-linux-x86_64-glibc23/bin/mysqld --defaults-file=./my.cnf ...
$ kill -11 2656
$ bin/mysqld_safe: line 137:  2656 Segmentation fault      (core dumped) ...
100304 16:46:43 mysqld_safe Number of processes running now: 0
100304 16:46:43 mysqld_safe mysqld restarted

When specified it states "core dumped" and file exists.

When I remove the option from my.cnf  (i.e. core-file is not enabled) No message is provide, and no core produced. 

Suggested fix:
Change default value in docs, or specify is this has changed in different versions of mysql.
[5 Mar 2010 4:31] Valeriy Kravchuk
Thank you for the documentation request.
[5 Mar 2010 16:46] Paul Dubois
Thank you for your bug report. This issue has been addressed in the documentation. The updated documentation will appear on our website shortly, and will be included in the next release of the relevant products.

You're correct, the default is FALSE.