July 24, 2014

Check for MySQL slave lag with Percona Toolkit plugin for Tungsten Replicator

A while back, I made some changes to the plugin interface for pt-online-schema-change which allows custom replication checks to be written. As I was adding this functionality, I also added the –plugin option to pt-table-checksum. This was released in Percona Toolkit 2.2.8. With these additions, I spent some time writing a plugin that allows Percona […]

Failover with the MySQL Utilities: Part 2 – mysqlfailover

In the previous post of this series we saw how you could use mysqlrpladmin to perform manual failover/switchover when GTID replication is enabled in MySQL 5.6. Now we will review mysqlfailover (version 1.4.3), another tool from the MySQL Utilities that can be used for automatic failover. Summary mysqlfailover can perform automatic failover if MySQL 5.6′s […]

High Availability with MySQL Fabric: Part I

In our previous post, we introduced the MySQL Fabric utility and said we would dig deeper into it. This post is the first part of our test of MySQL Fabric’s High Availability (HA) functionality. Today, we’ll review MySQL Fabric’s HA concepts, and then walk you through the setup of a 3-node cluster with one Primary and two […]

How to identify and cure MySQL replication slave lag

Here on the Percona MySQL Support team, we often see issues where a customer is complaining about replication delays – and many times the problem ends up being tied to MySQL replication slave lag. This of course is nothing new for MySQL users and we’ve had a few posts here on the MySQL Performance Blog […]

How to monitor ALTER TABLE progress in MySQL

While working on a recent support issue as a Percona Support Engineer,  I got one question from a customer asking how to monitor ALTER TABLE progress. Actually, for MySQL 5.5 and prior versions, it’s quite difficult to ALTER the table in a running production environment especially for large tables (with millions records). Because it will rebuild and lock the table […]

10 MySQL settings to tune after installation

When we are hired for a MySQL performance audit, we are expected to review the MySQL configuration and to suggest improvements. Many people are surprised because in most cases, we only suggest to change a few settings even though hundreds of options are available. The goal of this post is to give you a list […]

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 […]

Schema changes – what’s new in MySQL 5.6?

Among many of the improvements you can enjoy in MySQL 5.6, there is one that addresses a huge operational problem that most DBAs and System Administrators encounter in their life: schema changes. While it is usually not a problem for small tables or those in early stages of product life cycle, schema changes become a […]

Galera Flow Control in Percona XtraDB Cluster for MySQL

Last week at Percona Live, I delivered a six-hour tutorial about Percona XtraDB Cluster (PXC) for MySQL.  I actually had more material than I covered (by design), but one thing I regret we didn’t cover was Flow control.  So, I thought I’d write a post covering flow control because it is important to understand. What […]

Percona XtraBackup 2.1.0 for MySQL beta now available

Percona is glad to announce the release of Percona XtraBackup 2.1.0 for MySQL beta on April 22, 2013. Downloads are available from our download site here. For this BETA release, we will not be making APT and YUM repositories available, just base deb and RPM packages This is an BETA quality release and is not […]