The next presentation by Piotr Biel from Percona was on Multi-Master Manager for MySQL.

The introduction included a discussion of the popular MySQL HA solutions including:

• MySQL Master-slave replication with failover
• MMM managed bi-directional replication
• Heartbeat/SAN
• Heartbeat/DRBD
• NDB Cluster

A key problem that was clarified in the talk is the discussion of Multi-Master and this IS NOT master-master. You only write to a single node. With MySQL is this critical because MySQL replication does not manage collision detection.

The MMM Cluster Elements are:

• monitoring node
• database nodes

And the Application Components are:

• mon
• agent
• angel

MMM works with 3 layers.

• Network Layer – uses a virtual IP address, related to servers, not …

The slides for my presentation at FOSDEM 2010 are now available online at slideshare. In this presentation I describe a successful client implementation with the result of 10x performance improvements. My presentation covers monitoring, reviewing and analyzing SQL, the art of indexes, improving SQL, storage engines and caching.

The end result was a page load improvement from 700+ms load time to a a consistent 60ms.

10x Performance Improvements – A Case Study View more presentations from Ronald Bradford.

Following the opening keynote “Dolphins, now and beyond”, Marc Delisle presented on “State of phpMyAdmin”.

phpMyAdmin is an DBA administration tool for MySQL available today in 57 different languages. This is found today in many distributions, LAMP stack products and also in cpanel. The product is found at http://phpmyadmin.net.

There are current two versions, the legacy 2.x version to support older php 3.x & 4.x, The current version 3.x is for PHP 5.2 or greater.

The current UI includes some new features including.

• calendar input for date fields
• meta data for mime types e.g images, which is great for showing the output as an image, otherwise blob data
• Relational designer with the able to show and create foreign keys …

I had the honor of opening the day at the MySQL developer room at FOSDEM 2010 where I had a chance to talk about the MySQL product and community, now and what’s happening moving forward.

For those that missed the talk, my slides are available online at Slideshare however slides never due justice to some of the jokes including:

• What do you consider? the Blue Pill, or the Red Pill
• Why think two dimensionally, how about the Green Pill
• Emerging Breeds with performance enhancing modifications

Dolphins Now And Beyond – FOSDEM 2010 View more presentations from …

Those of you that know the documentation well will be aware of the old page we used to have for the MySQL documentation. It was huge, and over the years we’d done a number of things to try and improve the layout and make it easier to find what you wanted. We had in-age links to jump to the different documentation types, and the old topic table that allowed you to jump to specific parts of the documentation. The problem was that the more documentation that we produced (and there are over a thousand docs in various formats now), the bigger the page got. When we added the individual topic guides, for example, we trebled the size of the page by adding the links for each individual topic guide. Ultimately that makes it increasingly difficult for you guys to find what you are looking for, despite the quick links and other elements. We’ve now changed all this and split the single, big, monolithic …

Those of you that know the documentation well will be aware of the old page we used to have for the MySQL documentation. It was huge, and over the years we’d done a number of things to try and improve the layout and make it easier to find what you wanted. We had in-age links to jump to the different documentation types, and the old topic table that allowed you to jump to specific parts of the documentation.

The problem was that the more documentation that we produced (and there are over a thousand docs in various formats now), the bigger the page got. When we added the individual topic guides, for example, we trebled the size of the page by adding the links for each individual topic guide.

Ultimately that makes it increasingly difficult for you guys to find what you are looking for, despite the quick links and other elements.

We’ve now changed all this and split …

I have been upgrading more MySQL database instances recently and have found a few more potential gotchas, which if you are not careful, can potentially be rather nasty. These are not documented explicitly by MySQL, so it may be handy for you to know if you have not come across this type of thing before.

Most of the issues are those related to upgrading MySQL instances which are replicated, either the master servers or the slaves. Some seem specific to the rpm packages I am using (MySQL enterprise or MySQL advanced rpms), though others are not.

Take care upgrading a 5.0 master when you have 5.1 slaves

It is not a good idea to run a mixed major version of mysql in a replicated environment so why would I be doing this? If you work in a replicated environment and have several slaves then it is recommended that you upgrade the slaves first. I work with quite a few slaves so the process of upgrading them all takes longer …

The MySQL configuration file, e.g. /etc/my.cnf has a number of different section headings including [mysql], [mysqld], [mysqld_safe]. It is important that you ensure you put the right variables into the right section. For example, the following my.cnf configuration file will not operate as the user probably expects.

[mysqld]
...
log-bin=mysql-bin
server-id=1
query_cache_size = 100M
query_cache_type = 1

...

[mysqld_safe]
...
key_buffer_size=600M
skip-innodb
...

In this example, this configuration does not give you a MyISAM key buffer of 600M, it’s actually the default of 8M.

mysql> show global variables like 'key_buffer_size';
+-----------------+---------+
| Variable_name   | Value   |
+-----------------+---------+
| key_buffer_size | 8388600 |
+-----------------+---------+

Be sure to add the right options to the [mysqld] section.

What I didn’t know until yesterday was that some programs read from …

I hit this interesting problem last night on 5.0.51a.

mysql> use information_schema;
mysql> desc routines;
ERROR 1 (HY000): Can't create/write to file '/home/tmp/#sql_fea_1.MYD' (Errcode: 24)
mysql> show create table routines\G
*************************** 1. row ***************************
       Table: ROUTINES
Create Table: CREATE TEMPORARY TABLE `ROUTINES` (
  `SPECIFIC_NAME` varchar(64) NOT NULL default '',
  `ROUTINE_CATALOG` varchar(512) default NULL,
  `ROUTINE_SCHEMA` varchar(64) NOT NULL default '',
  `ROUTINE_NAME` varchar(64) NOT NULL default '',
  `ROUTINE_TYPE` varchar(9) NOT NULL default '',
  `DTD_IDENTIFIER` varchar(64) default NULL,
  `ROUTINE_BODY` varchar(8) NOT NULL default '',
  `ROUTINE_DEFINITION` longtext,
  `EXTERNAL_NAME` varchar(64) default NULL,
  `EXTERNAL_LANGUAGE` varchar(64) default NULL,
  `PARAMETER_STYLE` varchar(8) NOT NULL default '',
  `IS_DETERMINISTIC` varchar(3) NOT NULL default '',
  `SQL_DATA_ACCESS` varchar(64) NOT …

My talk on 10x performance improvements – A case study has just been approved for the 2010 MySQL Conference. This will be my 5th straight year speaking at the MySQL conferences. For those in Europe wanting a sneak peek I am also speaking at FOSDEM 2010 in Brussels on Feb 7th where I’ll be giving an abridged version.

As an independent MySQL consultant, my work generally covers performance tuning and scalability and sometimes database architecture. Often however my work involves a review of a given problem and recommendations (immediate, short and long term). I’m rarely involved in the full implementation and generally do not see the full fruits of the proposed work.

Recently however I was able to work with a client, first in resolving …