Galera Cluster has the ability to add new nodes to the cluster by handling internally the transfer of the entire dataset to the new node. The same procedure, called State Snapshot Transfer (SST), applies to nodes that are rejoining the cluster after being down for a longer period of time.

A lot of operations happen during SST and there are various things that could go wrong. This article describes how to configure our server optimally for SST and how to debug any issues that arise.

The Basics

Let’s first consider all the items that play a role in the preparation and configuration of SST.

Selecting an SST Method

Galera Cluster supports several different methods for performing SST so, before adding a new node, it is worth examining the alternatives:

• rsync is the default method and requires the least amount of setup. Its disadvantage is that the donor node remains locked for all …

We are big fans of automation which is also one of the reasons why we started TwinDB. We want to remove the pain around manual redundant jobs and automate them so that you can focus on what is important for your business.

Why Chef?

Awesome Chef

Chef is a great example of how automation can be successfully applied to infrastructure such that your infrastructure becomes easily deployable, manageable, testable and well documented. Whenever, I talk about the benefits of using Chef, I greatly highlight how writing Chef cookbooks essentially documents your infrastructure. Isn’t it great to have a well documented infrastructure, that anyone can reference to? How many times have I not heard someone tell me how they have no idea how a particular service was deployed, or what was deployed on a particular machine? Many many times, …

With MySQL 5.7 there will be many improvements and changes. The most valuable ones are:

1. “General Tablespace” feature -> From now you can place tables to separate tablespaces. Prior, on our hands there were only “System TableSpace” and “InnoDB file per table” options.

Check for further reading: General Tablespaces Create statement: Create TableSpace

2. Resizing InnoDB Buffer Pool online -> for changing innodb_buffer_pool_size variable restart is required prior to MySQL 5.7, from now we can change buffer pool size without restart dynamically. Read Documentation -> …

This Log Buffer Edition cuts through the crowd and picks some of the outstanding blog posts from Oracle, SQL Server and MySQL.

Oracle:

• Continuous Delivery (CD) is a software engineering approach in which teams keep producing valuable software in short cycles and ensure that the software can be reliably released at any time.
• Query existing HBase tables with SQL using Apache Phoenix.
• Even though WebLogic with Active GridlLink are Oracle’s suggested approach to deploy Java applications that use Oracle Real Applications Clusters (RAC), …

MariaDB 10.0.20 was recently released, and is available for download here:

https://downloads.mariadb.org/mariadb/10.0.20/

This is the eleventh GA release of MariaDB 10.0, and 21st overall release of MariaDB 10.0.

There were no major functionality changes, but there was one security fix, 6 crashing bugs fixed, some general upstream fixes, and quite a few bug fixes, so let me cover the highlights:

• Security Fix: Client command line option –ssl-verify-server-cert (and MYSQL_OPT_SSL_VERIFY_SERVER_CERT option of the client API) when used together with –ssl will ensure that the established connection is SSL-encrypted and the MariaDB server has a valid certificate. This fixes CVE-2015-3152.
• Crashing …

This is the first of two articles on sampling queries effectively. The second part is here.

Sampling is hard. This is the title of a talk I gave at a meetup in Boston a few weeks back. But what’s so hard about sampling anyway?

To begin with, let’s clarify what I mean by sampling. It’s a bit ambiguous because sampling could apply to a few different things one does with time series data. In this context, I’ll be talking about capturing individual events from a large, diverse set of events (queries).

Here’s a picture of a simple stream of events over time.

Notice that they are not all the same–some of them are higher or lower than others. This is a simple illustration of some variability in the stream.

The way VividCortex generates query insight is by computing metrics about the …

In the MySQL team we are currently discussing if we should deprecate the integer display width in numeric types. For example:

CREATE TABLE my_table (
 id INT(11) NOT NULL PRIMARY KEY auto_increment
);

The (11) does not affect the storage size of the data type, which for an INT will always be 4 bytes. It affects the display width.
Our rationale for proposing this should be deprecated is that it is a common source of confusion amongst users.

We are …

Percona is glad to announce the release of Percona Server 5.5.44-37.3 on July 1, 2015. Based on MySQL 5.5.44, including all the bug fixes in it, Percona Server 5.5.44-37.3 is now the current stable release in the 5.5 series.

Percona Server is open-source and free. Details of the release can be found in the 5.5.44-37.3 milestone on Launchpad. Downloads are available …

Percona is glad to announce the release of Percona Server 5.6.25-73.0 on July 1, 2015. Download the latest version from the Percona web site or from the Percona Software Repositories.

Based on MySQL 5.6.25, including all the bug fixes in it, Percona Server 5.6.25-73.0 is the current GA release in the Percona Server 5.6 series. Percona Server is open-source and free – and …

Wed, 2015-07-01 12:54anderskarlsson

It was a very long time since I wrote something in this blob, but I have been very busy this spring with MariaDB on Power. This has been a lot of work, but also a lot of fun. So, what is this MariaDB on Power thing all about, well I wrote an introduction to the Power platform late last year. Since then a lot of things has happened.

One thing is that several service providers out there have adopted Power8 as a platform. To be honest, this really isn't sexy, but it is useful and as a user of one of these services, you will just see the same old Linux you are used to, but potentially it is more powerful and reliable. One such provider is OVH, whose service is more known as RunAbove. If you want to try it, you can do so for …