If you are planning to upgrade or make any configuration change on your MySQL database the first advice usually is: – Benchmark! How should we do that benchmark? People usually run generic benchmark tools like sysbench, tpcc or mysqlslap that are good to know the number of transactions per seconds that a database can do [...]
Released: Percona Toolkit 2.1.5
Although Percona Toolkit 2.1.4 was recently released, we soon after found and fixed a couple of bugs concerning how pt-table-checksum works with Percona XtraDB Cluster: pt-table-checksum 2.1.4 doesn’t detect diffs on Percona XtraDB Cluster nodes pt-table-checksum 2.1.4 miscategorizes Percona XtraDB Cluster-based slaves as cluster nodes There was also a bug affecting pt-table-sync –version-check, and the [...]
Distro Packages, Pre-built Binaries or Compile Your Own MySQL
I’ve been helping customers deploy and maintain MySQL (and variants) for the last couple of years and it has always been interesting to hear customer thoughts on how they want their servers installed. It has also been asked many times not only by our support and consulting customers, but widely from different forums and blogs [...]
New variable slave_max_allowed_packet for slave servers
One month ago I wrote about how a big read_buffer_size could break the replication. The bug is not solved but now there is an official workaround to ease this problem using a new configuration variable: slave_max_allowed_packet This new variable will be available in 5.1.64, 5.5.26, and 5.6.6 and can establish a different limit on the [...]
News Flash: SQL Injection Still a Problem
The threat of SQL injection has appeared prominently in the news recently: An SQL injection vulnerability resulted in an urgent June bugfix release of Ruby on Rails 3.x. Make sure you upgrade if you use Rails 3.0, 3.1, or 3.2! Also you should disable mass assignment in any Rails project. Yahoo! Voices was hacked in July. The [...]
Find unused indexes
I wrote one week ago about how to find duplicate indexes. This time we’ll learn how to find unused indexes to continue improving our schema and the overall performance. There are different possibilites and we’ll explore the two most common here. User Statistics from Percona Server and pt-index-usage. User Statistics User Statistics is an improvement [...]
MySQL Upgrade Webinar Questions Followup
I did a Webinar about MySQL Upgrade – Best Practices Yesterday and there were some questions we could not answer during Webinar, following Jay’s Lead I decided to post them as a Blog Post. Q: Can you go directly MySQL 5.0 to 5.5 for MyISAM tables? MyISAM have not been getting any significant development since [...]
Find and remove duplicate indexes
Having duplicate keys in our schemas can hurt the performance of our database: They make the optimizer phase slower because MySQL needs to examine more query plans. The storage engine needs to maintain, calculate and update more index statistics DML and even read queries can be slower because MySQL needs update fetch more data to [...]
NO Security vulnerability in Percona Server / XtraDB Cluster provided binaries
Many of you heard of this nasty security vulnerability in MySQL, and as we are getting a lot of inquiries how does it affect Percona Server, I decided to address it in this post. The issue exists in the source code of MySQL 5.5.23 or earlier and MySQL 5.1.62 or earlier. The same is true [...]
Migrating to XtraDB Cluster Webinar follow up questions
Thanks to all who attended my webinar today. The session was recorded and will be available to watch for free soon here. There were a lot of great questions asked during the session, so I’d like to take this opportunity to try to answer a few of them: Q: Is there an easy way to [...]

