The latest from the MySQL community

March 3, 2014 By Severalnines

Hybrid replication, i.e. combining Galera and asynchronous MySQL replication in the same setup, became much easier with MySQL 5.6 and GTID. Although it was fairly straightforward to replicate from a standalone MySQL server to a Galera Cluster, doing it the other way round (Galera → standalone MySQL) was a bit more challenging. At least until MySQL 5.6 and GTID. 

There are a few good reasons to attach an asynchronous slave to a Galera Cluster. For one, long-running reporting/OLAP type queries on a Galera node might slow down an entire cluster, if the reporting load is so intensive that the node has to spend considerable effort coping with it. So reporting queries can be sent to a standalone server, effectively isolating Galera from the reporting load. In a belts and suspenders approach, an …

I spoke last month at linux.conf.au 2014 in Perth, Australia, and one of my sessions focused on the “Continuous Integration (CI) testing of Percona XtraDB Cluster (PXC)” at the Developer,Testing, Release and CI miniconf.

Here is the video of the presentation:

Here is the presentation itself:

Percona XtraDB Cluster before every release: Glimpse into CI testing from Raghavendra PrabhuBelow is a rough transcript of the talk:

This talk covered the continuous integration testing of the Galera cluster; specifically, Percona XtraDB Cluster (PXC), based on Galera, is taken into …

Lets start by considering a scenario where records are being inserted in a single auto-increment table via different nodes of a multi-master cluster. One issue that might arise is ‘collision’ of generated auto-increment values on different nodes, which is precisely the subject of this article.

As the cluster is multi-master, it allows writes on all master nodes. As a result of which a table might get same auto-incremented values on different nodes on INSERTs. This issue is discovered only after the writeset is replicated and that’s a problem!

Galera cluster suffers with the similar problem.

Lets try to emulate this on a 2-node Galera cluster :

1) On node #1:

MariaDB [test]> CREATE TABLE t1(c1 INT AUTO_INCREMENT PRIMARY KEY, c2 INT)ENGINE=InnoDB;
Query OK, 0 rows affected (0.07 sec)

MariaDB [test]> START TRANSACTION;
Query OK, 0 rows affected (0.00 sec)

MariaDB [test]> INSERT INTO t1(c2) VALUES (1);
Query …

February 18, 2014 By Severalnines

Virtual Machines are great, and very useful when trying out new software. However, they might be an unnecessarily heavyweight solution when testing clusters, especially if these consist of multiple nodes running exactly the same software. Each VM runs a full-blown OS image. On the other hand, Linux Containers (LXC) are an efficient alternative to OS-level virtualization and can run multiple isolated systems on a single host. Docker is a wrapper around LXC, it automates the deployment of applications inside containers. 

A notable advantage if you run with Docker + LXC is you can run many containers on a single host. They all share the same OS as the host, and when possible, the same binaries. Deployment can be extremely fast. Using Docker could be a good method if you want to spin multiple Galera nodes within a single host. 

In this post, we will create MySQL Galera Cluster …

The MariaDB project is pleased to announce the immediate availability of MariaDB Galera Cluster 5.5.35. This is a Stable release.

See the Release Notes and Changelog for detailed information on this release and the Galera page in the MariaDB Knowledge Base for general information about MariaDB Galera Cluster.

Download MariaDB Galera Cluster 5.5.35

Release Notes …

February 13, 2014 By Severalnines

Galera is slowly but surely establishing itself as a credible replacement for traditional MySQL master-slave architectures. 

The benefits are clear - a true multi-master InnoDB setup with built-in fail-over, potentially across data centers. 

But how do you migrate? Does the schema or application change? What are the limitations? Can migration be done online, without service interruption? What are the potential risks, and how to address those?

Webinar: Migrating to MySQL, MariaDB Galera and/or Percona XtraDB Cluster

Tuesday, March 11th 2014

Register now - Europe/MEA/APAC

Register now - North …

After my presentation at FOSDEM I got a few questions regarding our Galera implementation and why we did things the way we want. First of all, the slides: Spil Games @ FOSDEM: Galera Replicator IRL from spil-engineering Second of all, the questions I got: Q: Why first copy all the data to a new MySQL […]

The post Follow up on FOSDEM appeared first on Spil Games Engineering.

February 4, 2014 By Severalnines

Great news for Percona customers! We are thrilled to announce our partnership with Percona. Effective immediately, Percona customers will be able to enjoy the advanced automation, monitoring and cluster management capabilities of ClusterControl. Percona will be bundling, with its Cluster support contracts, Percona ClusterControl - a privately branded version of ClusterControl Community. Together we're providing support for the full stack, from Percona XtraDB Cluster to management tools, giving customers one number to call. 

For anyone who has deployed, managed or monitored a mission-critical database cluster, you will know that having the right tools can really make a difference. This is exactly our goal with ClusterControl, with a focus on operational management from day one. In only a few clicks, ClusterControl provides customers the ability to deploy Galera-based MySQL Clusters in private …

February 3, 2014 By Severalnines

Liferay is an open-source content management system written in Java. It is used by a number of high traffic sites, as this survey suggests. 

Clustering Liferay and other components such as the database and the file system is a good way to handle the performance requirements of a high traffic site. The latest Liferay version has introduced features that simplify clustering, such as built-in support for Ehcache clustering, Lucene replication, read/write splitting capabilities for database (in case if you run on master-slave architecture) and support for various file systems for the portal repository. 

In this post, we are going to show you how to cluster Liferay in a multi-node load-balanced setup. The database backend will be based on Galera Cluster for MySQL, and the file …

MaxScale for the rest of us - Part 1 SkySQL released MaxScale as Open Source on github a few weeks ago. For some instructions on how to install and configure it, Ivan Zoratti has written a blog about that, and Mark Riddoch has written about why we need MaxScale here, but what I will try in a series of blogs is to describe what MaxScale is, in terms of what you can do with it, and to put it into context, so that you have an idea why you would want to install it in the first place. I will also show how to configure and manage MaxScale. This first post is a quick introduction to MaxScale.

So what is MaxScale then? Mark, and many others, call it a Proxy, and that is partly true, if …