Bug #51889 UPDATE locking table
Submitted: 9 Mar 2010 20:22 Modified: 29 Mar 2011 19:03
Reporter: Roberto Spadim (Basic Quality Contributor) Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Locking Severity:S1 (Critical)
Version:5.1.32 OS:Linux
Assigned to: CPU Architecture:Any
Tags: locking, qc

[9 Mar 2010 20:22] Roberto Spadim 
Description:
hello sometimes my table is locked, the problem.. it's a UPDATE query, that ended (just 1 row on table to be updated using primary key) 

the network:
2 computers
one running php+apache, one running mysql
a crossover 1gb/s ethernet cable from one to another (no ethenet errors on "dmesg", neither link down/up, the network is running ok)

How to repeat:
i don't know but it's a query that always happen

the query "show processlist" when every thing is locked:

43	2329040 	rdm 	172.18.0.5:43680 	raja_comercial 	Query 	350 	end 	UPDATE spamov SET data_prevista_embarque="2010-03-09 16:32:30" WHERE unidade_id=1004 AND lote_tipo='v' AND lote_spa=147338

Suggested fix:
??
to unlock i run 

FLUSH TABLES
and after:
UNLOCK TABLES
[9 Mar 2010 21:53] Roberto Spadim 
create table / insert data at this url:

http://www.spadim.com.br/lock 09032010.zip

tnkx
[10 Mar 2010 7:47] Sveta Smirnova 
Thank you for the report.

I can not repeat described behavior with that single query.

What are additional circumstances needed to repeat this error? Do you have other threads connected in time when UPDATE runs? Could you please connect gdb to mysqld in time when it hangs, then run `thread apply all bt full`? Please also send us your configuration file.

Also try current version 5.1.44 and inform us if problem still exists.
[10 Mar 2010 13:16] Roberto Spadim 
ok, i will update version, since it's old, and wait the error to occur again, i don't know why it's happen, but the only think that i see is a "end" status, and anothers threads waiting this to end, with "locked" status
[10 Mar 2010 17:30] Sveta Smirnova 
Thank you for the feedback.

We will wait results of your testing of new version.
[10 Apr 2010 23:00] 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".
[29 Mar 2011 19:03] Roberto Spadim 
working without problems now
i changed the network card, the linux kernel, and the mysql version to 5.5

i will close this bug, it´s don´t happen anymore