April 23, 2014

An argument for not using mysqldump

I have a 5G mysqldump which takes 30 minutes to restore from backup.  That means that when the database reaches 50G, it should take 30×10=5 hours to restore.  Right?  Wrong.

Using netcat to copy MySQL Database

This is mainly a cheat sheet for me to remember. Nothing rocket science. It often makes sense to use netcat/nc to copy MySQL database between hosts in trusted networks. It bypasses encryption overhead of SSH and depending on configuration can be significantly faster. Also note MySQL should be down when you copy data unless you’re […]

What does Using filesort mean in MySQL?

If you were interviewing to work at Percona, and I asked you “what does Using filesort mean in EXPLAIN,” what would you say? I have asked this question in a bunch of interviews so far, with smart people, and not one person has gotten it right. So I consider it to be a bad interview […]

Confusing MySQL Replication Error Message

I already wrote about some MySQL Error Messages which are confusing, here is one more:

After setting up new slave Server I’m getting error log file flooded with messages like this and there is no hint in the message what would explain what is wrong. In fact the issue in this case is (because […]

Using Sphinx as MySQL data retrieval accelerator

I’ve run into the following thread couple of days ago: Basically someone is using sphinx to perform search simply on attributes (date, group etc) and get sorted result set and claiming it is way faster than getting it with MySQL. Honestly I can well believe it for cases when you want to know number of […]

Using LVM for MySQL Backup and Replication Setup

If someone asks me about MySQL Backup advice my first question would be if they have LVM installed or have some systems with similar features set for other operation systems. Veritas File System can do it for Solaris. Most SAN systems would work as well. What is really needed is ability to create atomic snapshot […]

Using UNION to implement loose index scan in MySQL

One little known fact about MySQL Indexing, however very important for successfull MySQL Performance Optimization is understanding when exactly MySQL is going to use index and how it is going to do them. So if you have table people with KEY(age,zip) and you will run query something like SELECT name FROM people WHERE age BETWEEN […]

Percona Live 2014 behind; MySQL ahead

I started using MySQL 11 years ago.  That’s not too long compared to other people in the industry, but nonetheless here’s my perspective on the state of the MySQL industry after attending Percona Live MySQL Conference & Expo 2104. In short, the attitude around MySQL has changed from “Does it work?” to “Is it fast […]

How to find bugs in MySQL

Finding bugs in MySQL is not only fun, it’s also something I have been doing the last four years of my life. Whether you want to become the next Shane Bester (who is generally considered the most skilled MySQL bug hunter worldwide), or just want to prove you can outsmart some of the world’s best […]

‘Open Source Appreciation Day’ draws OpenStack, MySQL and CentOS faithful

To kick off the Percona Live MySQL Conference & Expo 2014, Percona held the first “Open Source Appreciation Day” on Monday, March 31st. Over 210 people registered and the day’s two free events focused on CentOS and OpenStack. The OpenStack Today event brought together members of the OpenStack community and MySQL experts in an afternoon of […]