August 1, 2014

What I learned while migrating a customer MySQL installation to Amazon RDS

Hi, I recently had the experience of assisting with a migration of a customer MySQL installation to Amazon RDS (Relational Database Service). Amazon RDS is a great platform for hosting your MySQL installation and offers the following list of pros and cons: You can scale your CPU, IOPS, and storage space separately by using Amazon […]

Failover with the MySQL Utilities – Part 1: mysqlrpladmin

MySQL Utilities are a set of tools provided by Oracle to perform many kinds of administrative tasks. When GTID-replication is enabled, 2 tools can be used for slave promotion: mysqlrpladmin and mysqlfailover. We will review mysqlrpladmin (version 1.4.3) in this post. Summary mysqlrpladmin can perform manual failover/switchover when GTID-replication is enabled. You need to have […]

Why %util number from iostat is meaningless for MySQL capacity planning

Earlier this month I wrote about vmstat iowait cpu numbers and some of the comments I got were advertising the use of util% as reported by the iostat tool instead. I find this number even more useless for MySQL performance tuning and capacity planning. Now let me start by saying this is a really tricky and deceptive number. Many […]

Using UDFs for geo-distance search in MySQL

In my previous post about geo-spatial search in MySQL I described (along with other things) how to use geo-distance functions. In this post I will describe the geo-spatial distance functions in more details. If you need to calculate an exact distance between 2 points on Earth in MySQL (very common for geo-enabled applications) you have at […]

Measure the impact of MySQL configuration changes with Percona Cloud Tools

When you make a change to your MySQL configuration in production it would be great to know the impact (a “before and after” type of picture). Some changes are obvious. For many variables proper values can be determined beforehand, i.e. innodb_buffer_pool_size or innodb_log_file_size. However, there is 1 configuration variable which is much less obvious for many people […]

Using MySQL 5.6 Performance Schema in multi-tenant environments

Hosting a shared MySQL instance for your internal or external clients (“multi-tenant”) was always a challenge. Multi-tenants approach or a “schema-per-customer” approach is pretty common nowadays to host multiple clients on the same MySQL sever. One of issues of this approach, however, is the lack of visibility: it is hard to tell how many resources (queries, disk, […]

Using InfiniDB MySQL server with Hadoop cluster for data analytics

In my previous post about Hadoop and Impala I benchmarked performance of analytical queries in Impala. This time I’ve tried InfiniDB for Hadoop (open-source version) on the modern hardware with an 8-node Hadoop cluster. One of the main advantages (at least for me) of InifiniDB for Hadoop is that it stores the data inside the Hadoop cluster but uses the […]

Errant transactions: Major hurdle for GTID-based failover in MySQL 5.6

I have previously written about the new replication protocol that comes with GTIDs in MySQL 5.6. Because of this new replication protocol, you can inadvertently create errant transactions that may turn any failover to a nightmare. Let’s see the problems and the potential solutions. In short Errant transactions may cause all kinds of data corruption/replication […]

Tips on benchmarking Go + MySQL

We just released, as an open source release, our new percona-agent (, the agent to work with Percona Cloud Tools. This agent is written in Go. I will give a webinar titled “Monitoring All MySQL Metrics with Percona Cloud Tools” on June 25 that will cover the new features in percona-agent and Percona Cloud Tools, […]

GTIDs in MySQL 5.6: New replication protocol; new ways to break replication

One of the MySQL 5.6 features many people are interested in is Global Transactions IDs (GTIDs). This is for a good reason: Reconnecting a slave to a new master has always been a challenge while it is so trivial when GTIDs are enabled. However, using GTIDs is not only about replacing good old binlog file/position […]