Bug #64140 mysqladmin debug writes out spurious lock entries to error log
Submitted: 27 Jan 2012 0:09 Modified: 27 Jan 2012 7:28
Reporter: Jason Becker Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server Severity:S3 (Non-critical)
Version:5.1.61, 5.5 OS:Any (CentOS 5.7)
Assigned to: Paul Dubois CPU Architecture:Any
Tags: mysqladmin
Triage: Needs Triage: D2 (Serious)

[27 Jan 2012 0:09] Jason Becker
Description:
Issuing the command "mysqladmin debug" writes out what appears to be spurious lock entries in the error log. The entries are described as "Current locks" but if you do a SHOW PROCESSLIST there are no locks.

How to repeat:
Install MySQL Community Server 5.1.61 and Client Utilities.

(I ran mysql_secure_installation immediately after the RPM install out of habit.)

Issue a mysqladmin debug command.

Look in the error log, in this case /var/lib/mysql/$HOSTNAME.err - you will see the following:

-BEGIN-

Status information:

Current dir: /var/lib/mysql/
Running threads: 1  Stack size: 262144
Current locks:
lock: 0x158df488:

lock: 0x158cddb8:

lock: 0x158c2b48:

lock: 0x158b7f98:

lock: 0x158ab6d8:

lock: 0x158a4de8:

lock: 0x15895ab8:

lock: 0x1588fbe8:

lock: 0x15887d58:

Key caches:
default
Buffer_size:       8384512
[snip]

-END-

Suggested fix:
Don't write out these spurious locks, or, if they aren't spurious, provide more information about them and/or document what they are.
[27 Jan 2012 1:40] Jason Becker
correct synopsis typo
[27 Jan 2012 7:28] Valeriy Kravchuk
Yes, one can get these kind of output even on server without any active connections. I think our manual should really explain this (and other details of mysqladmin debug output) at http://dev.mysql.com/doc/refman/5.5/en/mysqladmin.html.