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Got a packet bigger than ‘slave_max_allowed_packet’ bytes and binlog_format=STATEMENT|MIXED

Since version 5.1.64 MySQL introduces a new variable named slave_max_allowed_packet, which was introduced to allow large updates using row-based replication do not cause replication to fail when exceeded max_allowed_packet.

The problem is if you have you replication using binlog_format=STATEMENT or binlog_format=MIXED it ignores this option and use as limit for queries what is on max_allowed_packet variable but still reporting on slave_max_allowed_packet causing the IO_THREAD to report the wrong message.

Solution:
Run the …

I have been meaning to write this down for quite some time, but it always eluded me. When you are using Time Machine to back up your Mac, you get the chance of password-protecting your backups.

Whenever the machine is restarted you will have to unlock the disk by entering the password, unless you store the password for the backup disk in your keychain. For paranoia's sake (and to keep the password fresh in my memory, just in case) I do not store the password in the keychain.

Now, what happens quite regularly to me is this: I reboot the machine for some reason or other, and while it is doing that, I leave the room and do something else. Before I know it, maybe an hour has passed before I come back. In the meantime, the external Time Machine drive has gone to sleep, because it was not used for an extended period of time. On the screen, there is the password dialog dutifully waiting for me to unlock the protected volume.

As …

We’re always testing the latest versions of MySQL with most of the environments to make sure that we can find the critical issues before it goes to production. This wasn’t different with the 5.6 MySQL neither. We already started to play with this version in the summer. The first news were very promising. The performance gain is significant. However we have run into couple of errors. One of them was the

mysql_install_db problem with replicating environment

[root@hostname ~]# mysql_install_db --user=mysql --datadir=/mysql/data/

------------------------------------------------------------------------------------
Installing MySQL system tables...
121217 10:02:20 InnoDB: The InnoDB memory heap is disabled
121217 10:02:20 InnoDB: Mutexes and rw_locks use GCC atomic builtins
121217 10:02:20 InnoDB: Compressed tables use zlib 1.2.3
121217 10:02:20 InnoDB: Using Linux native AIO
121217 10:02:20 InnoDB: CPU supports crc32 instructions
121217 10:02:20 …

Recently I was discussing with some colleagues the possibility of consolidating some MySQL servers. While the servers are not heavily loading (averaging less than 1,000 queries a second) they are pretty large in terms of storage requirements. Each server has roughly 200 databases on each with approximatley 50 tables. Thats 10,000 tables per server.  Each server contains up to 1 terabyte of data so if you consolidated servers at a 10:1 ratio you would have 10 terabytes of data, 2,000 databases and 100,000 tables with 10,000 queries per second average load.

Alright, that's a lot. And without testing I don't know if it would work. It probably wouldn't.  But it might. And if it did, it would save the company a significant amount of money.  But, while discussing this,  someone brought up that open files limit might be a problem. Open files limit is the maximum number of files the …

For the week of August 24th, 2012: Everybody’s Preparing for OpenWorld Dispelling the Rumors of MySQL’s Impending Doom On Piracy of Design IOUG Podcast 24-AUG-2012 Rumors of MySQL’s Doom by Oracle / Design Piracy Subscribe to this Podcast (RSS) or … Continue reading →

We just ran into a nasty InnoDB bug that only seems to exist in MySQL 5.5.25:

An InnoDB update that modifies a rows primary key can trigger some recursive behavior that creates new rows until all disk space is exceeded. This does not affect all primary key updates in general but only gets triggered when a few other conditions are also met, so you're not too likely to run into it, but if you do your mysqld server will waste a lot of IO bandwidth and storage space on this and will usually eventually run out of disk space.

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I came across an interesting error reported on #mysql the other day. When I went through it with the reporter it looks like we uncovered up to two bugs in InnoDB (or rather XtraDB as it was Percona Server). I thought it might be useful to go through the error message, including the stack trace, to show that you don't need to be a developer to track down some useful information.

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There is a nice demo of  MySQL Bug 13510739 on Eric Romang's blog

I've published this blog to make this content available on planet.mysql.com.

I just want to share about a strange behavior of one of our MySQL server yesterday.
This server is a 5.1.50 MySQL server on debian 4.0 (Yes, I know…)

When a “mysqld got signal 6” error occurred yesterday, the MySQL server crashed and didn’t want to restart.
Then, I found these informations in the error log file :

/usr/local/mysql/bin/mysqld: File '*** glibc detected ***
malloc():memory corruption: 0x00002aac2d5ab460 ***' not found (Errcode: 2)
120306 17:19:47 [ERROR] Failed to open log (file '*** glibc detected ***
malloc():memory corruption: 0x00002aac2d5ab460 ***', errno 2)
120306 17:19:47 [ERROR] Could not open log file
120306 17:19:47 [ERROR] Can't init tc log
120306 17:19:47 [ERROR] Aborting

120306 17:19:47 InnoDB: Starting shutdown...
120306 17:19:53 InnoDB: Shutdown completed; log sequence number 55 1061584593
120306 17:19:53 [Note] /usr/local/mysql/bin/mysqld: Shutdown complete

Great, let see …

Some days ago while I’m looking for what are saying about a mysql.com server down I found a twitter bug:

Is not a big deal, to repeat this bug you must follow these steps:

1. Find any term, in this case “mysql.com” then in results looking for a word that have the search term as a part of them (ex dev.mysql.com) and select the a part or entire word:

2. Press Ctrl + C,  some HTML codes appear from nowhere:

3. Do it again and again, you will see an strange twit like this:

I’m using Firefox 8.0  under Ubuntu, but you will …