This is the second part in a two-part series comparing Virident’s vCache to FlashCache. The first part was focused on usability and feature comparison; in this post, we’ll look at some sysbench test results. Disclosure: The research and testing conducted for this post were sponsored by Virident. First, some background information. All tests were conducted [...]
Percona Monitoring Plugins 1.0.3 for MySQL now available
Percona is glad to announce the release of Percona Monitoring Plugins 1.0.3 for MySQL — high-quality components to add enterprise-grade MySQL monitoring and graphing capabilities to your existing in-house, on-premises monitoring solutions. The components are designed to integrate seamlessly with widely deployed solutions such as Nagios and Cacti, and are delivered in the form of [...]
MySQL 5.6 Compatible Percona Toolkit 2.2 Released
A new Percona Toolkit series has been released: Percona Toolkit 2.2 for MySQL 5.6. Several months in the making and many new features, changes, and improvements make this a great new series. It replaces the 2.1 series for which we plan to do only one more bug fix release (as 2.1.10) then retire. 2.2 is [...]
MySQL 5.5 lock_wait_timeout: patience is a virtue, and a locked server
Like Ovais said in Implications of Metadata Locking Changes in MySQL 5.5, the hot topic these days is MySQL 5.6, but there was an important metadata locking change in MySQL 5.5. As I began to dig into the Percona Toolkit bug he reported concerning this change apropos pt-online-schema-change, I discovered something about lock_wait_timeout that shocked me. From the [...]
Percona Toolkit Webinar followup Q&A
First, a thank you to everyone who attended the webinar Today, I appreciate your time and nice comments. As promised, here are answers to questions that couldn’t be answered during the talk: Q: How do you install the tools? The manual has full details, but it’s important to know that the latest release for [...]
Percona XtraDB Cluster: Multi-node writing and Unexpected deadlocks
Percona XtraDB Cluster (PXC) and the technology it uses (Galera) is an exciting alternative to traditional MySQL replication. For those who don’t know, it gives you: Fully Synchronous replication with a write latency increase equivalent to a ping RTT to the furthest node Automatic cluster synchronization, both incremental and full restores The ability to read [...]
Percona XtraDB Cluster reference architecture with HaProxy
This post is a step-by-step guide to set up Percona XtraDB Cluster (PXC) in a virtualized test sandbox. I used Amazon EC2 micro instances, but the content here is applicable for any kind of virtualization technology (for example VirtualBox). The goal is to give step by step instructions, so the setup process is understandable and [...]
InnoDB’s gap locks
One of the most important features of InnoDB is the row level locking. This feature provides better concurrency under heavy write load but needs additional precautions to avoid phantom reads and to get a consistent Statement based replication. To accomplish that, row level locking databases also acquire gap locks. What is a Phantom Read A [...]
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 [...]

