Seeing as it looks like 5.5 is shortly about to go GA I thought I’d give it a run and see how well it works. The only way really to test it is to give it a bit of load and look for things which break. That I did with the 5.5.6-rc community rpms, compared to the 5.1 advanced rpms I usually run.

My colleagues, Ben and Peter, found a horrible problem which means that I can’t use this even for any real usage on my real servers. See: bug#57095 for all the gory details. Thanks to them both for finding the problem and then digging down and figuring out the real cause. Sometimes developers work a long way from the database so their errors don’t translate into something I can really look at in the database. They delved into the problem and then found the cause and a nice easy test case which I could report to MySQL.

After a couple of days of running this was …

Internally MySQL uses various methods to manage (or, block) concurrent access to shared structures within the server - the most common being mutexes (or Mutual Exclusion locks), RW Locks, or Semaphores. Each have slightly different properties on how different threads are allowed to interact when trying to access these synchronization points.

There has been much written on the various hot spots in the server around these locking/blocking constructs over the past couple of years, so I won’t go further in to that here. See the excellent blogs from Mikael or Dimitri from within …

Yesterday, Sept. 19, 2010 at the inaugural MySQL Sunday event at Oracle OpenWorld, we announced the MySQL 5.5 Release Candidate. The MySQL 5.5 release candidate helps improve the performance and scalability of applications across multiple operating environments, including Windows, Linux, and Mac. Enhancements include:

Improved performance and scalability:

• MySQL Server and InnoDB have been enhanced to provide optimum performance and scalability when running on the latest multi-CPU and multi-core hardware and operating systems.
• InnoDB is now the default storage engine for MySQL Server, delivering ACID transactions, referential integrity, and crash recovery.

Higher availability:

• New semi-synchronous replication improves failover reliability by allowing the …

UPDATE: New room assignments for the MySQL Cluster and Replication Enhancements sessions

With the MySQL Sunday event at Oracle Open World rapidly approaching, and registrations to the event 10x higher than originally forecast, I thought it would be a good time to highlight sessions that are specifically addressing MySQL high availability, including MySQL Cluster .

You can see details and logistics of all of the sessions here

MySQL Cluster
Andrew Morgan and I will be presenting the latest enhancements in the world of …

Oracle managed to score a major victory last week at the MySQL Conference by announcing performance gains of 200-360% in the forthcoming version 5.5.  This is a tremendous improvement and comes in part due to closer collaboration between what were historically two distinct (and occasionally competitive) groups: the InnoBase team and the MySQL Server team.  Bringing the InnoBase team under the direction of the MySQL Server team under Tomas Ullin is a great benefit not only to MySQL developers, but also for MySQL users.  No doubt these performance gains are a result of many months of hard work by not only Tomas, but also a good number of folks on both teams including guys like Mikael Ronstrum, Kojstja, Calvin Sun and others.  

Reaction to the new release has been positive in the community from the likes of …

EAVB_VFZUHIARHI To whom it may concern -

The mysqldump program can be used to make logical database backups. Although the vast majority of people use it to create SQL dumps, it is possible to dump both schema structure and data in XML format. There are a few bugs (#52792, #52793) in this feature, but these are not the topic of this post.XML output from mysqldumpDumping in XML format is done with the --xml or -X option. In addition, you should use the --hex-blob option otherwise the BLOB data will …

Ever since MySQL 5.5 beta has been announced by Edward Screven, Oracle’s chief corporate architect; there is lot of positive buzz (here, here, …) about the performance and scalability improvements added in this release. We should all be thankful to Michael Ronstrom (as most of the key developers are already working on different forks), who [...]

MySQL 5.5 Highlights - It's a lot faster! InnoDB

Multiple Buffer Pool Instances Multiple Rollback Segments Extended change buffering and purge scheduling Improved Log Sys and Flush List mutex Improved locking Improved statistics on InnoDB mutexes, rw-locks, threads and I/O operations.

Improved performance/scale with Win32, 64 Scales to 32 cores  Semi-synchronoous replication Performance

Good news: As you read this, you can very soon start downloading the first version of MySQL 5.5 from http://dev.mysql.com/downloads/.

Some things are the same as before, others are different. Let’s start by looking at the version string, SELECT VERSION();

mysql> SELECT VERSION();
+--------------+
| version()    |
+--------------+
| 5.5.0-m2-log |
+--------------+
1 row in set (0.00 sec)
mysql>

And let’s look at the highlights of the release notes, or better still, MySQL 5.5 in a nutshell in the manual on http://dev.mysql.com/doc/refman/5.5/en/mysql-nutshell.html. Top of the list is …