New in this release:
External PHP based binary log consumer. It wraps 'mysqlbinlog' and reads settings from an .ini file.
The consumer must be running in order to refresh views and collect table change logs.
MIN/MAX and COUNT(DISTINCT) are now supported, experimentally.
Many other improvements.

Ever been around a group of people discussing some technology and heard Cool-Whip phrases like this?

It’s not about MySQL versus PostgreSQL, it’s about using the right tool for the job.

Or how about this one?

You need to take the important factors into account before you decide whether [hot new fad] or [trusty old solution] is best suited for your application.

Both are signs that someone might be trying to sound important. In situations like this, I’ve noticed that the people I look up to usually don’t make weighty-sounding statements about other people’s systems. They talk about what they are qualified to talk about: either they say something about their own systems, or if it’s warranted and invited, they ask intelligent questions about other people’s systems.

People who only have vacuous generalities to contribute don’t talk about their own systems, because if they actually worked on …

For those of you interested in the open source database world, you will get a good in-depth look at Kontrollbase this month in the OSDB Magazine. Keith Murphy has been kind enough to give me pages 37 through 50 to tell you all about the history, current features, and plans for the future. It’s a [...]

It’s been hectic to find a good provider even with all of the choices out there these days but I’m happy to let you know that we settled on ServerBeach for the demo server and are back online. The page load testing is positive and quick, and all features are available for you to try. [...]

I am working with a client that is using managed hosting on dedicated servers. This has presented new challenges in obtaining the right permissions to undertake MySQL tasks but not have either ‘root’ or ‘mysql’ access and not have to involve a third party everytime.

Adding the following to the /etc/sudoers file enabled the ability to restart MySQL.

User_Alias      DBA = rbradfor, user2, etc
Host_Alias      DB_SERVERS = server1.example.com, server2.example.com, etc
Cmnd_Alias      MYSQL = /etc/init.d/mysqld, /usr/sbin/tcpdump

DBA DB_SERVERS = MYSQL

As you can see I also got tcpdump, which I find valuable to monitor via mk-query-digest.

Next, permissions for log files.

Dear interweb, if you have no idea what you’re writing about, keep it to yourself, don’t litter into the tubes. Some people may not notice they’re eating absolute crap and get diarrhea.

This particular benchmark has two favorite parts, that go with each other together really well:

I didnt change absolutely any parameters for the servers, eg didn’t change the innodb_buffer_pool_size or key_buffer_size.

And..

If you need speed just to fetch a data for a given combination or key, Redis is a solution that you need to look at. MySQL can no way compare to Redis and Memcache. …

Seriously, how does one repay for all the damage of such idiotic benchmarks?

P.S. I’ve ranted at benchmarks before, and will …

I wanted to compare the following DBs, NoSQLs and caching solutions for speed and connections. Tested the following

• Redis
• Memcached
• Tokyo Tyrant / Tokyo Cabinet
• MySQL 5.1.40 (MyISAM)
• MySQL 5.1.40 (with Innodb Plugin 1.0.4), compiled into source of MySQL

My test had the following criteria

• 2 client boxes
• All clients connecting to the server using Python
• Used Python's threads to create concurrency
• Each thread made 10,000 open-close connections to the server
• The server …

Désolé, il ne reste plus de place pour cette matinée dédiée à l'optimisation des performances MySQL.

Date : 24 novembre 2009

Session 1 : 9h30-10h45

• Architecture MySQL : Parsing, exécution, optimizer, query cache, binlog…etc
• Architecture Innodb : Clustered index, bufferpool, hash index, insert buffer, locking model, MVCC, recovery log, checkpoint…etc. Comparaison avec les autres moteurs de stockage (PBXT, MySQL Cluster) et bases de données (PostgreSQL, Oracle ..).

Pause/Café : 10h45-11h00.

Session 2 : 11h00-12h30

• Évolutions récentes : Google SMP patches,  XtraDB, Oracle innodb plugin 1.0.4
• Apports de MySQL 5.4
• Améliorations à venir :  Ahead flushing / Adaptive checkpoint,  …

Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable - innodb_open_files which defines how many files Innodb will keep open while working in innodb_file_per_table mode.

Unlike MyISAM Innodb does not have to keep open file descriptor when table is open - open table is purely logical state and appropriate .ibd file may be open or closed. Furthermore besides MySQL table_cache Innodb maintains its own (called data dictionary) which keeps all tables ever accessed since table start - there is no variable to control its size and it can take significant amount of memory in some edge cases. Percona patches though provide innodb_dict_size_limit to restrict …

Like I said earlier, every tiny change that the test suite reveals after code changes is significant. I caught a very subtle “bug” today in recent changes to mk-query-digest (a.k.a. mqd). If you like to read about subtle bugs, read on.

An mqd test on sample file slow023.txt began to differ after some pretty extensive code changes of late:

< # Query 1: 0 QPS, 0x concurrency, ID 0x8E38374648788E52 at byte 0 ________
---
> # Query 1: 0 QPS, 0x concurrency, ID 0x2CFD93750B99C734 at byte 0 ________

The ID which depends on the query’s fingerprint has changed. It’s very important that we don’t suddenly change these on users because these IDs are pivotal in trend analyses with mqd’s --review-history option. First some background info on the recent code changes and then the …