September 23, 2014

Prevent MySQL downtime: Set max_user_connections

One of the common causes of downtime with MySQL is running out of connections. Have you ever seen this error? “ERROR 1040 (00000): Too many connections.” If you’re working with MySQL long enough you surely have. This is quite a nasty error as it might cause complete downtime… transient errors with successful transactions mixed with […]

DBA 101: Sometimes forgotten functionality in the MySQL client

The MySQL client has some functionalities some of us never use. Why would you use them and what is the added value of this? Every DBA and developer has had a moment when he or she needs to connect to a MySQL database using the command line tool. Therefore I’ve written down an explanation of […]

Innotop: A real-time, advanced investigation tool for MySQL

GUI monitoring tools for MySQL are not always suitable for all our needs or situations. Most of them are designed to provide historical views into what happens to our database over time rather then real-time insight into current MySQL server status. Excellent free tools for this include Cacti, Zabbix, Ganglia, Nagios, etc. But each of […]

The top 5 proactive measures to minimize MySQL downtime

I’m happy to announce that the recording for my recent webinar “5 Proactive Measures to Minimize MySQL Downtime” is now available, along with the slides. They can both be found here. My webinar focused on the top 5 operational measures that prevent or reduce downtime — along with the related business impact in a significant […]

Recovering temporal types in MySQL 5.6: TIME, TIMESTAMP and DATETIME

MySQL 5.6 introduces a new feature – microseconds resolution in some temporal types. As of 5.6.4 TIME, TIMESTAMP and DATETIME can have a fractional part. To create a field with subseconds you can specify precision in brackets: TIME(3), DATETIME(6) etc. Obviously, the new feature requires the format change. All three types may now have a […]

MySQL Webinar: 5 proactive measures to help minimize MySQL downtime, July 17

Failure is an unavoidable part of IT life, but it does not always have to imply MySQL service downtime. In the years I have been working at Percona, I have been involved in many customer emergency cases, and I have seen a good number of problems that could have been avoided or alleviated if relatively […]

Summertime Percona MySQL training update

Now that June has arrived it is time to plan what you will do over the summer months. In addition to your summer vacation plans, give thought to MySQL training for you and your team. Summer is the time to brush up on those critical skills needed to ensure all systems are ready for the holiday […]

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 […]

Zero-Downtime Schema Changes In MySQL

The recording of yesterday’s webinar, as well as a PDF of my slide deck, is now available. You can watch the recording and get the slides here. I got a lot of questions, and did not have enough time to answer all of them, so let me try to answer some of the remaining questions […]

Time for Zero Administration effort at MySQL ?

Preparing Optimizing MySQL Configuration talk for Percona Live in Washington,DC I noticed how many Variables did MySQL get over years – it is pushing 400 these days even if we do not count variables/options which do not have matching SHOW VARIABLES value, and settings done by changing tables rather than command line options (like much […]