Jul 03, 2008 |
Benchmarks, Insight for Developers
Recently I had a customer ask me about loading two huge files into InnoDB with LOAD DATA INFILE. The goal was to load this data on many servers without putting it into the binary log. While this is generally a fast way to load data (especially if you disable unique key checks and foreign key […]
Jun 24, 2008 |
Percona Events
If you’re a Perl and/or Python expert (preferably both), Percona may have a job for you. We’re looking to either hire or sponsor significant development efforts for some open-source tools for MySQL, including but not limited to Maatkit and the Master-Master Replication Manager. This could be full-time or part-time, depending on the person and what […]
Jun 23, 2008 |
Insight for DBAs
How many of you use the MySQL command-line client? And did you know about the pager command you can give it? It’s pretty useful. It tells MySQL to pipe the output of your commands through the specified program before displaying it to you. MySQL Command-line Pager Here’s the most basic thing I can think of […]
May 31, 2008 |
Insight for DBAs
Do you have skip_name_resolve set in your /etc/my.cnf? If not, consider it. DNS works fine, until it doesn’t. Don’t let it catch you off guard. Do you really need to restrict MySQL users based on hostnames? If you don’t, you should probably disable this feature of MySQL’s authentication system. You never know when your hosting […]
May 26, 2008 |
Insight for DBAs
A while ago I wrote about how to make MySQL replication reliable, part of which is to eliminate temporary tables. The idea is this: if a slave is stopped (or crashed) while a temporary table is open and is then restarted, the temporary table doesn’t exist anymore, and the slave will have problems trying to […]
May 24, 2008 |
Insight for DBAs
Much has been written about the new InnoDB pluggable storage engine, which Innobase released at the MySQL conference last month. We’ve written posts ourselves about its fast index creation capabilities and the compressed row format, and how that affects performance. One of the nice things they added in this InnoDB release is INFORMATION_SCHEMA tables that […]
May 14, 2008 |
Insight for DBAs
Recently I had an interesting surprise with concurrent inserts into a MyISAM table. The inserts were not happening concurrently with SELECT statements; they were blocking and the process list was filling up with queries in Locked status. My first thought was that the customer had deleted from the table, which leaves “holes” in the middle […]
Apr 28, 2008 |
Insight for Developers
In my post on estimating query completion time, I wrote about how I measured the performance on a join between a few tables in a typical star schema data warehousing scenario. In short, a query that could take several days to run with one join order takes an hour with another, and the optimizer chose […]
Apr 22, 2008 |
Insight for DBAs
Have you ever run a query in MySQL and wondered how long it’ll take to complete? Many people have had this experience. It’s not a big deal until the query has been running for an hour. Or a day and a half. Just when IS that query going to finish, anyway? There are actually a […]