Bug #49641 mysqldump: Error 2013: Lost connection to MySQL server during query when dumping

• Submitted: 12 Dec 2009 20:59
• Modified: 13 Dec 2009 9:10
• Reporter: Tomas Dalebjörk
• Status: Duplicate
• Category: MySQL Server: Backup
• Severity: S2 (Serious)
• Version: 5.0.45-7.el5
• OS: Linux (RHEL 5.3)
• CPU Architecture: Any
• Tags: ERROR 2013, mysqldump

[12 Dec 2009 20:59] Tomas Dalebjörk

Description:
We get the following error:

mysqldump: Error 2013: Lost connection to MySQL server during query when dumping table `tsm_test_db` at row: 1609975

We are running several "mysqldump" commands in parallel to speedup.
But we have the opertunity to do this in sequence too.

Please help me...

How to repeat:
mysqldump --user=root --password=XXX --opt --single-transaction --routines --flush-logs  tsm_test_db

[12 Dec 2009 21:53] MySQL Verification Team

Thank you for the bug report. Duplicate of bug: http://bugs.mysql.com/bug.php?id=46103.

[13 Dec 2009 9:09] Tomas Dalebjörk

Thanks for the update.
If I run the "mysqldump" command in sequential (and not in parallel; the backup was working).

Sequential means: One database at a time from the same MySQL server.
Parallel means: Many databases at the same time from the same MySQL server.

Question: Could the parameter: --max_allowed_packet solved this problem?

Regards Tomas

[13 Dec 2009 9:10] Tomas Dalebjörk

Updated the Versions in the bug report

[6 Jul 2011 15:12] Rick James

I agree that mysqldump should do a better job of avoiding timeouts.

mysqldump is very intense on disk reads and network traffic.  I suspect that your 'parallel' dumps could each be running slow because of bottlenecking on one of these.

A workaround (for Tomas) would be to limit how many dumps are running simultaneously -- limit to where the disk and/or network is nearly saturated.