October 23, 2014

Recovery after DROP [ TABLE | DATABASE ]

In your recovery practice we often face the problem when data lost by execution DROP TABLE or DROP DATABASE statement. In this case even our InnoDB Data Recovery tool can’t help, as table / directory with files was deleted (if you have innodb-file-per-table). And the same for MyISAM, all .MYD / .MYI / .frm – […]

Inexpensive SSDs for Database Workloads

The cost of SSDs has been dropping rapidly, and at the time of this writing, 2.5-drives have reached the 1TB capacity mark.  You can actually get inexpensive drives for as little as 60 cents per GB. Even inexpensive SSDs can perform tens of thousands of IOPs and come with 1.5M – 2M hous MTBF and […]

Recovery after DROP & CREATE

In a very popular data loss scenario a table is dropped and empty one is created with the same name. This is because  mysqldump in many cases generates the “DROP TABLE” instruction before the “CREATE TABLE”:

If there were no subsequent CREATE TABLE the recovery would be trivial. Index_id of the PRIMARY index of […]

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 […]

Upcoming webinar on Data Recovery for MySQL

I’ll be giving a 40-50 minute long webinar on 26th of April on data recovery for MySQL. Almost every long serving DBA has been faced with the task of recovering data from a database, whether it be via user error such as a erroneously dropped table or from Hardware or Software failure. In this Webinar […]

Paris OpenStack Summit Voting – Percona Submits 16 MySQL Talks

MySQL plays a critical role in OpenStack. It serves as the host database supporting most components such as Nova, Glance, and Keystone and is the most mature guest database in Trove. Many OpenStack operators use Percona open source software including the MySQL drop-in compatible Percona Server and Galera-based Percona XtraDB Cluster as well as tools such as Percona XtraBackup and Percona Toolkit. […]

Examining the TokuDB MySQL storage engine file structure

As we know different storage engines in MySQL have different file structures. Every table in MySQL 5.6 must have a .frm file in the database directory matching the table name. But where the rest of the data resides depends on the storage engine. For MyISAM we have .MYI and .MYD files in the database directory […]

How to improve InnoDB performance by 55% for write-bound loads

During April’s Percona Live MySQL Conference and Expo 2014, I attended a talk on MySQL 5.7 performance an scalability given by Dimitri Kravtchuk, the Oracle MySQL benchmark specialist. He mentioned at some point that the InnoDB double write buffer was a real performance killer. For the ones that don’t know what the innodb double write […]

A technical WebScaleSQL review and comparison with Percona Server

The recent WebScaleSQL announcement has made quite a splash in the MySQL community over the last few weeks, and with a good reason. The collaboration between the major MySQL-at-scale users to develop a single code branch that addresses the needs of, well, web scale, is going to benefit the whole community. But I feel that […]

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 […]