Bug #7106 Query Cache Corrupted, Malformed Packet Errors
Submitted: 8 Dec 2004 15:38 Modified: 8 Jan 2005 17:11
Reporter: Anthony Caravello Email Updates:
Status: No Feedback Impact on me:
None 
Category:MySQL Server Severity:S2 (Serious)
Version:4.1.5-4.1.7 OS:Linux (Fedora Core 3/RedHat 9)
Assigned to: CPU Architecture:Any

[8 Dec 2004 15:38] Anthony Caravello
Description:
After a short period of time, specific queries start to return errors.  And once a query returns an error, it will continue to do so until MySQL is restarted.

While usually a 2027 Malformed Packet error is returned, sometime the query returns fine, correct number of rows, but no data in the fields, seemingly do to incorrect field names returned.

If I execute the same query as a different user, it will return data correctly.  If I restart server problem will go away, and when it returns, it is generally not with the same query, but will appear in some other query.

The problem originally surfaced using MySQL Control Center.  Rows were returned, but the field names were gibberish.  Restarting server fixed this temporarily.

But now it is appearing more often in web sites I host using a slightly older Apache 2.0.49/MySQL 4.0.12 client/PHP 5.0.0RC2 in use 1 year *and* a newer Apache 2.0.52/MySQL 4.1.7 client/PHP 5.0.2 in use 3 months.

I am now attempting to disable the query cache to see if it eliminates the problem.  Have already tried moving data to a diff. partition and restarting server.

MySQL Server Hardware: Dell PowerEdge 2450 with dual Intel 733Mhz CPU's, 512MB RAM, PERC 3/si RAID 1. 

Configuration: Basically the large my.cnf distributed with soft.  Installed MySQL Standard binaries.

How to repeat:
Repeated use of query cache.  My server probably handle a few thousand queries /day, not a tremendous amount, but within hours I will see error notifications.
[8 Dec 2004 16:56] Sergei Golubchik
please check whether http://bugs.mysql.com/6511 is the same bug...
[8 Dec 2004 17:11] Anthony Caravello
Yes, this looks like the same exact problem as bug #6511.  Will upgrade my older client and see if problem is resolved.

Thank You
[14 Feb 2005 22:54] 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".