During the last couple of months I have been involved in an unusually high amount of performance audits for e-commerce applications running with Magento. And although the systems were quite different, they also had one thing in common: the MySQL query cache was very useful. That was counter-intuitive for me as I’ve always expected the query cache to be such a bottleneck that response time is better when the query cache is turned off no matter what. That lead me to run a few experiments to better understand when the query cache can be helpful.

Some context

The query cache is well known for its contentions: a global mutex has to be acquired for any read or write operation, which means that any access is serialized. This was not an issue 15 years ago, but with today’s multi-core servers, such serialization is the best way to kill performance.

However from a performance …

VividCortex is sponsoring and exhibiting at PGConf Silicon Valley November 17 - 18th. Stop by our booth to get a free product demo and see how we can revolutionize your database monitoring.

Baron Schwartz will also be speaking on Analyzing PostgreSQL Network Traffic with vc-pgsql-sniffer, so be sure to learn from his experience.

Click here for more details and registration.

VividCortex is sponsoring and exhibiting at PGConf Silicon Valley November 17 - 18th. Stop by our booth to get a free product demo and see how we can revolutionize your database monitoring.

Baron Schwartz will also be speaking on Analyzing PostgreSQL Network Traffic with vc-pgsql-sniffer, so be sure to learn from his experience.

Click here for more details and registration.

If you run multiple MySQL instances on a Linux machine, chances are good that at one time or another, you’ve ended up connected to an instance other than what you had intended. It’s certainly happened to me, and I submitted Bug#76512 to deal with the cause which affects me most commonly – that the mysql client will silently ignore the –port option and connect using the default Unix socket instead when the host is “localhost” (default).  We’ve recently discussed ways we can make this behavior less surprising to users, and though we’re now past the second RC of MySQL Server 5.7, we’re contemplating making these changes in future 5.7 releases.  Please let us know your thoughts!

Here are the basic principles of what we intend to change:

Explicit –protocol option rules all

If a user provides an explicit …

Hi all, it is time again to do another preview release of MySQL Group Replication, the plugin that brings multi-master update everywhere to MySQL, like we described in Hello World post.

We are very proud to do the third preview release of MySQL Group Replication, which introduces new exciting features, please enjoy the highlights!…

Here is version 0.4.0 of the MySQL Group Replication plugin, our solution that gives you virtual synchronous updates on any member of a MySQL server group. With this new version you can expect a bunch of bug fixes and new features.…

The multi master plugin for MySQL is here. MySQL Group Replication provides virtually synchronous updates on any member in a group of MySQL servers, with conflict handling and automatic group membership management and failure detection.

You can read about all MySQL Group Replication features following the tag MySQL Group Replication.

On this blog post we will present the packages the MySQL Group Replication 0.4.0 offers and what are the tasks that you need to perform to install the plugin on the MySQL server.

Packages

Go to http://labs.mysql.com/, choose MySQL Group Replication on the release menu. You will see two files there:

1. mysql-group-replication-0.4.0-labs.tar.gz
2. mysql-group-replication-0.4.0-labs-el6.x86_64.tar.gz …

MySQL 5.7 comes with many changes. Some of them are better explained than others.

I wanted to see how many changes I could get by comparing SHOW VARIABLES in MySQL 5.6 and 5.7.
The most notable ones are:

• binlog_format: the default is now ROW. This variable affects the format of the binary log, whether you use it as a backup complement or for replication, the change means bigger binary logs and possibly side effects.
• …

Why Should I Be Reading This?

To better understand how the MySQL Server functions, how to monitor the relevant server events, and find out what’s new in MySQL 5.7.8.

What’s Special About the Audit Plugin API?

Picking the right API for your new plugin is probably the most important design decision a plugin author will need to make.…

The MariaDB project is pleased to announce the immediate availability of MariaDB 10.0.21 and 5.5.45. These are both Stable (GA) releases.

Download MariaDB 10.0.21

Release Notes Changelog What is MariaDB 10.0?

Download MariaDB 5.5.45

Release Notes Changelog What is …