September 15, 2014

Followup questions to ‘What’s new in Percona XtraDB Cluster 5.6′ webinar

Thanks to all who attended my webinar yesterday.  The slides and recording are available on the webinar’s page.  I was a bit overwhelmed with the amount of questions that came in and I’ll try to answer them the best I can here. Q: Does Percona XtraDB Cluster support writing to multiple master? Yes, it does.  However, […]

MySQL server memory usage troubleshooting tips

There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory usage for MySQL. As a Percona support engineer, I’m seeing many issues regularly related to heavy server loads – OR OOM killer got invoked and […]

Renaming database schema in MySQL

One of the routine tasks for a DBA is renaming database schemas, and as such MySQL added a command to carry out that purpose called “RENAME DATABASE <database_name>”. However this command just made it through a few minor releases before being discontinued (from MySQL 5.1.7 to 5.1.23). Here’s a link to the reference manual regarding […]

How can we bring query to the data?

Baron recently wrote about sending the query to the data looking at distributed systems like Cassandra. I want to take a look at more simple systems like MySQL and see how we’re doing in this space. It is obvious getting computations as closer to the data as possible is the most efficient as we will […]

How to move the InnoDB log sequence number (LSN) forward

This post focuses on the problem of the InnoDB log sequence number being in the future. Preface: What is an InnoDB log sequence number? The Log sequence number (LSN) is an important database parameter used by InnoDB in many places. The most important use is for crash recovery and buffer pool purge control. Internally, the InnoDB […]

Here’s my favorite secret MySQL 5.6 feature. What’s yours?

MySQL 5.6 has a great many new features, including, but certainly not limited to a number of performance improvements. However, besides the widely talked-about features such as InnoDB support for full text search, optimizer, performance schema improvements and GTID, there are also a few tiny improvements that nobody cared to mention. One such feature is…

Changing an async slave of a PXC cluster to a new Master

Async and PXC A common question I get about Percona XtraDB Cluster is if you can mix it with asynchronous replication, and the answer is yes!  You can pick any node in your cluster and it can either be either a slave or a master just like any other regular MySQL standalone server (Just be […]

Migrating between MySQL schemas with Percona Xtrabackup

Recently, I was working with a client that asked about using Percona Xtrabackup to take a snapshot of a particular MySQL schema and then reload it with a different schema name on the same server.  It caught me off guard because I’d never really thought about it – typically, I’ve used Xtrabackup simply to clone […]

Replication in MySQL 5.6: GTIDs benefits and limitations – Part 1

Global Transactions Identifiers are one of the new features regarding replication in MySQL 5.6. They open up a lot of opportunities to make the life of DBAs much easier when having to maintain servers under a specific replication topology. However you should keep in mind some limitations of the current implementation. This post is the […]

How to create a new (or repair a broken) GTID based slave with Percona XtraBackup

Percona XtraBackup 2.0.7 has been published with support for GTID based replication. As promised, here is the step-by-step guide on how to create a new GTID based slave (or repair a broken one) using XtraBackup. The process is pretty straightforward. 1- Take a backup from any server on the replication environment, master or slave:

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