Iostat is a very handy tool to help you investigating what kind of performance problems you have. Especially your databases can cause a lot of troubles to your I/O system and thus it would be very nice if every DBA has installed iostat on all of his MySQL database servers.

Unfortunately most of the Linux distributions do NOT install iostat by default. This causes often unfortunate situations when you are in a MySQL consulting engagement or have a MySQL support case and ask the customer for the output of iostat. In some cases they are not willing or allowed to install iostat on their production systems on the fly (even though I never have seen it causing troubles during or after the installation).

Further iostat is also not too easy to find because is is hidden in the sysstat package. But iostat can be easily post-installed as follows:

 shell> sudo apt-get install sysstat
 shell> yum install sysstat
 shell> rpm -i …

If you’d like some improvements to the Cacti templates (MySQL, Apache, Memcached, and more) I’ve been maintaining, please make your voice heard — either write to the mailing list, or post a new issue (or comment on an existing one) on the issue list. I’ve got a bunch of work underway, including a test suite for ss_get_by_ssh.php.

Related posts:

1. Version 1.1.6 of Better Cacti Templates released I’ve
2. Version 1.1.2 of improved Cacti templates released I’ve
3. …

I have written about the new support for group commit in the InnoDB plugin and the lack of support for it in the binlog. I will attempt to describe how commit is done for MySQL 5.1 and the InnoDB plugin.

The current code can limit performance depending on your workload. I think it is reasonable to claim that group commit is still broken when using the InnoDB plugin and the binlog is enabled despite the changes to enable it for the plugin when the binlog is diabled.

There are two performance problems in the code listed below. I think my description is correct but I have gotten this wrong in the past.

1. Group commit for the binlog is neither done nor possible. It is not possible because Innodb locks prepare_commit_mutex during the time at which the binlog …

If you’d like some improvements to the Cacti templates (MySQL, Apache, Memcached, and more) I’ve been maintaining, please make your voice heard – either write to the mailing list, or post a new issue (or comment on an existing one) on the issue list. I’ve got a bunch of work underway, including a test suite for ss_get_by_ssh.php. VividCortex is the startup I founded in 2012. It’s the easiest way to monitor what your servers are doing in production and I consider it far superior to Cacti.

In this article I am responding to many parts of Monty’s post at http://monty-says.blogspot.com/2009/12/help-keep-internet-free.html which are just plain not true, or are exaggerations.

I will give my own answers to the self-interview questions Monty provides, as I feel he is using his name and popularity to spreading fear that is not warranted.

Q: Why don’t you trust that Oracle would be a good owner of MySQL?

I cannot say whether or not Oracle would kill MySQL. However, I have already stated I believe Oracle will not kill MySQL. This is based on the fact that Oracle has had the chance to kill MySQL for several years, by making InnoDB proprietary, and has not.

Folks can debate …

It is my pleasure to be your Program Chair, for the O’Reilly MySQL Conference & Expo 2010, to be held April 12-15 2010, in Santa Clara, California.

It is of course, not something I embark on alone. I have a program committee, comprising of some amazing folk: Brian Aker, Kaj Arno, Roland Bouman, Sheeri K. Cabral, Robin Schumacher, Baron Schwartz, and Jeff Wiss.

I can highly encourage you to submit a proposal. You have till January 27, 2010, which basically means, less than a month, so get cracking! I also can highly recommend you to register as an attendee.

I’ll talk more about the processes, et al, in …

The latest in the whole Save MySQL campaign: HelpMySQL.org. Monty has a really long blog post on how to help keep the Internet free. When you read that, scroll down towards “Q: How do the proposed remedies benefit your company, Monty Program Ab?” Understand that Monty is doing this for the love of the codebase and the project that is MySQL…

Totally love the copywriting here: Customers pay the bill: Oracle can have Sun but not MySQL. There’s been a lot of FUD in the last few months, but I suggest you read the …

Answering questions asked on the site.

Rick McIntosh asks:

I have two tables, one with a list of spreadsheets (a) and the other with a list of the column headings that show in the spreadsheets (b).

This is a solution that I've seen a few people have trouble with now, so I want to make more people aware of it:

Say you have some items that can have any of a set of associated values. These could be a list flags, it could be keywords or tags. This is often seen as the anti-pattern known as "Comma Separated List of Doom" (CSLoD). Naive developers will often create something like the following:

create table cslod ( id serial, vals varchar(255) );
insert into cslod values (NULL, "cyan,yellow" );
select * from cslod;
+----+-------------+
| id | vals        |
+----+-------------+
|  1 | cyan,yellow |
+----+-------------+

I know that most people reading this already understand this is bad but let me re-iterate: Please please please don't do this! It will be very very difficult to write meaningful queries later.

The natural solution …

The mysqldump filter was created with this need in mind. It allows you to remove all DEFINER clauses and eventually replacing them with a better one.
For example:

mysqldump --no-data sakila | dump_filter --delete > …