Bug #63935 Crash in MDL_lock
Submitted: 5 Jan 2012 13:41 Modified: 11 Feb 2012 18:37
Reporter: Ben Mildren Email Updates:
Status: No Feedback Impact on me:
Category:MySQL Server: Locking Severity:S2 (Serious)
Version:5.5.12 OS:Solaris (5.10 i86)
Assigned to: CPU Architecture:Any

[5 Jan 2012 13:41] Ben Mildren
120103  8:55:54 - mysqld got signal 6 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help diagnose
the problem, but since we have already crashed, something is definitely wrong
and this may fail.

It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 147532668 K
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x112d4cbc0
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...
/lib/amd64/libc.so.1:__lwp_kill+0xa [ Signal 6 (ABRT)]
Please read http://dev.mysql.com/doc/refman/5.1/en/resolve-stack-dump.html
and follow instructions on how to resolve the stack trace.
Resolved stack trace is much more helpful in diagnosing the
problem, so please do resolve it

Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (124c08bd0): SHOW TRIGGERS FROM `db1`
Connection ID (thread ID): 155030

The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
120103 08:56:30 mysqld_safe mysqld restarted
120103  8:56:30 [Note] Plugin 'FEDERATED' is disabled.
120103  8:56:30 InnoDB: The InnoDB memory heap is disabled
120103  8:56:30 InnoDB: Mutexes and rw_locks use Solaris atomic functions
120103  8:56:30 InnoDB: Compressed tables use zlib 1.2.3
120103  8:56:30 InnoDB: Initializing buffer pool, size = 60.0G
120103  8:57:00 InnoDB: Completed initialization of buffer pool
120103  8:57:01 InnoDB: highest supported file format is Barracuda.
InnoDB: Log scan progressed past the checkpoint lsn 4342326497036
120103  8:57:01  InnoDB: Database was not shut down normally!
InnoDB: Starting crash recovery.

How to repeat:
This has only occurred once in several months of operation on this version, so it seems likely it could be due to a very specific set of circumstances.. ..the bug hasn't occurred since, however I will feedback if there is another occurrence.
[5 Jan 2012 15:11] Valeriy Kravchuk
Please, check if the same problem still happens with a newer version, 5.5.19.
[7 Jan 2012 23:37] Davi Arnaut
Looks like a exception thrown by new, probably because of out of memory.
[12 Feb 2012 1:00] Bugs System
No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".