Multi-Threaded Slave

MySQL 5.6 has now been declared Generally Available (i.e. suitable for production use). This is a very exciting release from a MySQL replication perspective with some big new features. These include:

• Global Transaction Identifiers (GTIDs) – a unique identifier that is used accross your replication topology to identify a transaction. Makes setting up and managing your cluster (including the promotion of a new master) far simpler and more reliable.
• Multi-threaded slaves (MTS) – Increases the performance of replication on the slave; different threads will handle applying events to different databases.
• Binary Log Group Commit – Improves replication performance on the master.
• …

There are many good things in the upcoming MySQL 5.6 release. One thing that caught my eye early on was the ability to start the server with InnoDB set to a read only mode.

A few months ago Todd Farmer wrote about this ability from the perspective of setting up an instance on read-only media (InnoDB now works with read-only media). And I encourage you to read that post first.
I decided to test this from a data warehouse perspective (as Sunny Bains points out in a comment to Todd's post). I used machines I have available: 1 OL6 desktop running 5.6.9 and 1 MacBook Pro running 10.8.

First thing to try was adding the innodb_read_only parameter to the config file on an instance I already had running on the Linux box. My setting:

[mysqld]
user = mysql
port = 5602
…

Following our Percona MySQL University event in Raleigh,NC Percona MySQL University comes to South America! We’ll have a Full day FREE MySQL Technical Educational events in Montevideo on February 5th, 2013 and Buenos Aires on February 7th.

I’m very excited to bring these events to MySQL Community in Uruguay and Argentina. This is my first trip to South America and it looks like it is going to be a lot of fun!

With Percona MySQL University events, we focus on MySQL Education for broad group of users. We’ve specially prepared talks that will be interesting for people just starting with MySQL to experienced MySQL developers and DBAs. So …

FOSDEM 2013

The Free and Open source Software Developers’ European Meeting (FOSDEM) is a two-day event organized by volunteers to promote the widespread use of Free and Open Source software. As in previous years, there is a dedicated stream of MySQL Sessions. On Saturday (2nd Feb) evening there’s a MySQL community dinner and then we’ve a packed program from 9:15 through 17:30 on Sunday (3rd Feb).

FOSDEM 2013 is a free event and there’s no requirement to pre-register – just get yourself along to Brussels.

This year I’ll be making a presentation introducing MySQL Cluster. Several of my colleagues from …

Percona Toolkit 2.1.8

Percona Toolkit 2.1.8 was released today and the new version comes with some pretty cool news: Beta support for MySQL 5.6 (which as you might know is also in beta).

In addition to various bug fixes, Percona Toolkit 2.1.8 also offers beta support for Percona XtraDB Cluster (PXC). Version 2.1.8 continues the trend of solid bug fix releases, and all 2.1 users are encouraged to upgrade.

You can download Percona Toolkit 2.1.8 here.  (More info on Percona Toolkit). Users who plan on running the tools on Percona XtraDB Cluster or MySQL 5.6 are advised to upgrade. …

Sergey Glukhov (Gluh) recently wrote an interesting blog about InnoDB secondary key improvements in MySQL 5.6. His blog isn't aggregated to planet.mysql.com but certainly deserves some attention. 
Here it is: InnoDB, extended secondary keys.

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 …

There are so many exciting new features in MySQL 5.6 that I almost don't know where to start. To mention a few, MySQL's multi-core scalability has been significantly improved to meet modern hardware, InnoDB has better index statistics, much better performance, and online ALTER, replication has multi-threaded slaves and …

With a handful of exceptions, few people deliberately choose to deploy MySQL on read-only media – but there are cases where being able to access InnoDB data that way comes in handy.  As it happened, I had exactly this need a few months back, and the excellent InnoDB development team at Oracle has recently implemented this feature in MySQL 5.6.

First, some background.  We had a need to migrate  legacy systems from a 3rd party data center into new corporate data centers.  These systems were redundant, but we wanted to retain access to the data for archival purposes.  All went well, except one small detail:  Because the machines were originally housed outside the new data center, we weren’t allowed to stand up the servers inside the new data center – except in read-only mode.

Therein was the problem – we had many GB worth of data stored in MySQL using InnoDB, and we could access the data files – …

I previously published stored programs to help implement a (more) comprehensive password policy in MySQL 5.6, building on the password complexity plugin now available in MySQL 5.6.  This proof-of-concept has been expanded recently, and the updated package is available here.  There’s a few notable changes to the earlier version:

Moved all created objects out of mysql system database

The mysql database is meant for system tables, and I try to keep everything not directly managed by the MySQL server out of that database.  The initial proof-of-concept implementation violated this principal – the update corrects this by creating and using a new password_policy database …