Now that MySQL 5.7 has become GA it’s a good time to highlight how much performance has improved in replication since the 5.6 era. This blog post will focus on the performance of the multi-threaded slave applier (MTS), and about it’s scalability in particular.…

MySQL 5.7 has been recently declared Generally Available and in it there is a set of new replication features. Over the last 6 years MySQL replication has evolved at a tremendous pace. MySQL 5.6 brought us a lot of new replication features, many that were ground breaking and yes, sometimes controversial.…

With the release of 10.1.8, MariaDB takes a next step. MariaDB 10.1 is now considered a stable release.

MariaDB 10.1 has a couple of main themes:

• Security
• High Availability
• Scalability

During the last few years there have been many request for more security features in MariaDB. Actually it’s a trend in general. Since open source software is getting more attractive all the time, more functionality is wanted in areas where proprietary software typically has been leading. This is especially true for databases. In addition data privacy is a very hot topic.

The big new thing in security for MariaDB 10.1 is a complete data at rest encryption solution. The encryption that now is in use originates from Google’s encryption patch. It has now been migrated into MariaDB 10.1. The …

A common way to implement point in time recovery capability is:

to regularly do a full backup of a database, and to save the binary logs of that database (or from its master if doing backups on a slave).

When point in time recovery is required you need to:

restore a backup, and apply the binary logs up to the point of recovery.

(Step # 2 and # b above are the ones that will be simplified

Update 2016-01-30: restarting the IO_THREAD might be considered useful in some situations (avoiding MDEV-9138).  Look for "in contrast, if the IO thread was also stopped first" in MDEV-6589 for more information.

In a previous post, I listed some sequences of commands that you should not run on a MariaDB slave that is lagging and which is using the GTID protocol.  Those are the following (do not

In the spirit of sharing war stories and avoiding others to do the same mistakes as I did, here are some sequences of commands that you should avoid to run on a MariaDB slave that is lagging and which is using the GTID protocol.  Remember, do not run those because...

So, those bad commands are the following:

"STOP SLAVE; START SLAVE UNTIL ...;", or "STOP SLAVE; START SLAVE;" (to remove an

During the PerconaLive conference in Amsterdam, I attended a session where I heard a good piece of advice about using GTID. It amounts to: look at SHOW SLAVE STATUS output, and if you see more than one line in the Executed_Gtid_Set field, this tells you immediately if someone has written on a slave database.
This is good advice. Let's dissect it. Here is what a regular slave looks like, when nobody has messed up with it:

SHOW SLAVE STATUS\G
*************************** 1. row ***************************
 [...]
             Master_Server_Id: 1
                  Master_UUID: 00013454-1111-1111-1111-111111111111
             Master_Info_File: mysql.slave_master_info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more …

We remember when we first started auditing MySQL servers, there were very few tools available.  In one of our early big gigs, we were battling serious performance issues for a client.  At the time, tuning-primer.sh was about the only tool available that could be used to diagnose performance bottlenecks.  Fortunately, with a lot of manual interpolation of the raw data it presented, we were able to find the issue with the server and suggest how to resolve them.  For that we are very thankful.  It was a first step in analyzing MySQL status variables, minimizing the number of formulas to learn and calculate by hand.  Obviously doing it by hand takes forever!

Now fast-forward to today.  Unfortunately, not much has changed.  Many DBAs and developers are still using open source tools such as tuning-primer, mysqltuner.pl, mysqlreport, and so on.  Don’t get the wrong; those tools have …

For companies that live and die by their databases, a one-shot backup isn’t really the perfect solution. Typically for such companies (think Yahoo! or Google), database access is a near-constant process, and database content changes continually, often on a second-by-second basis. Data replication, which involves continual data transfer between two (or more) servers to maintain a replica of the original database, is a better backup solution for these situations.

MySQL supports two (or three, depending on how you look at it) different methods of replicating databases from master to slave. All of these methods use the binary log; however, they differ in the type of data that is written to the master’s binary log.

• Statement-based replication Under this method, the binary log stores the SQL statements used to …

Replication in MySQL is the dynamic process of synchronizing data between a primary (master) database server and one or more secondary (slave) database servers in near-real time. Using this process, it’s possible to create copies of one or more databases so that even if the primary server fails, data can still be recovered from one of the secondary servers.

Replication is essential for many applications, and the lack of replication support was a major drawback to MySQL compared to other relational database management systems (RDBMSs). MySQL 3.23 was the first version to introduce replication support, and support has improved continually in subsequent versions. However, MySQL is still best suited for one-way replication, where you have one master and one or more slaves.

TIP

As much as possible, try to use the same version of MySQL for both the master and slave server(s). A version …