MySQL Replication is useful and easy to setup. It is used for very different purposes. For example: split read and writes run data mining or reporting processes on them disaster recovery Is important to mention that a replication server is not a backup by itself. A mistake on the master, for example a DROP DATABASE [...]
How FLUSH TABLES WITH READ LOCK works with Innodb Tables
Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only is very short, just few seconds, yet the impact of FLUSH TABLES WITH READ LOCK can be quite large because [...]
Faster Point In Time Recovery with LVM2 Snaphots and Binary Logs
LVM snapshots is one powerful way of taking a consistent backup of your MySQL databases – but did you know that you can now restore directly from a snapshot (and binary logs for point in time recovery) in case of that ‘Oops’ moment? Let me show you quickly how. This howto assumes that you already [...]
How to Monitor MySQL with Percona’s Nagios Plugins
In this post, I’ll cover the new MySQL monitoring plugins we created for Nagios, and explain their features and intended purpose. I want to add a little context. What problem were we trying to solve with these plugins? Why yet another set of MySQL monitoring plugins? The typical problem with Nagios monitoring (and indeed with [...]
How to recover deleted rows from an InnoDB Tablespace
In my previous post I explained how it could be possible to recover, on some specific cases, a single table from a full backup in order to save time and make the recovery process more straightforward. Now the scenario is worse because we don’t have a backup or the backup restore process doesn’t work. How [...]
How to recover a single InnoDB table from a Full Backup
Sometimes we need to restore only some tables from a full backup maybe because your data loss affect a small number of your tables. In this particular scenario is faster to recover single tables than a full backup. This is easy with MyISAM but if your tables are InnoDB the process is a little bit [...]
Percona XtraDB Cluster Feature 1: High Availability
There and in coming posts I am going to cover main features of Percona XtraDB Cluster. The first feature is High Availability. But before jumping to HA, let’s review general architecture of the Percona XtraDB Cluster.
How To Test Your Upgrades – pt-upgrade
Upgrades are usually one of the biggest part of any database infrastructure maintenance. Even with enough planning something else can go bad after sending your production application to the version you’ve upgraded to. Let’s look at how one Percona Toolkit tool, pt-upgrade can help you identify what to expect and test your upgrades better which [...]
Fishing with dynamite, brought to you by the randgen and dbqp
I tend to speak highly of the random query generator as a testing tool and thought I would share a story that shows how it can really shine. At our recent dev team meeting, we spent approximately 30 minutes of hack time to produce test cases for 3 rather hard to duplicate bugs. Of course, [...]
Emulating global transaction ID with pt-heartbeat
Global transaction IDs are being considered for a future version of MySQL. A global transaction ID lets you determine a server’s replication position reliably, among other benefits. This is great when you need to switch a replica to another master, or any number of other needs. Sometimes you can’t wait for the real thing, but [...]

