It seems pretty common to find customers install DRBD for the wrong reasons. There are many pros/cons to compare DRBD to replication, but I've managed to cut down my spiel I give to customers to these two points:

• DRBD's aim (assuming replication mode C) is to provide 100% consistency, and then as much uptime as possible.
• MySQL Replication (with a manager such as MMM) aims to have 100% availability, at the potential loss of some data surrounding a failure.

So if you are installing DRBD with the aim of purely "availability", and are not worried about losing that last write on the crash to your master database that (hopefully) happens only once every few years, you may be using the wrong technology.

While the prized "1 minute failover" is possible in DRBD, it doesn't really explain the full picture. The typical crash …

The success of the "Your server for free this summer!" operation is such that we have decided to have another promotion, which will be an extension of the previous one.

The first 1,000 free servers were given out in less than one week! Given the number of requests that we have received, we have even opened 102 accounts in addition to what was planned. Only here is the problem: there are many of you on the waiting list and at Gandi, and we want to be able to please as many as possible

The new promotion will therefore begin today. We are once more offering 1,000 free servers though this time, for only one month. The promotion remains, of course, without any purchase necessary, and you are free to keep your server by adding hosting resources to your account, or to let them expire.

The promotion that allows you to benefit from 2 free months …

This is just a public service announcement (reminder?) that LenZ and Giuseppe are planning OpenSQL Camp 2009, this time in Europe, which is great. It'll be part of FrOSCon.

I wish I could say that I'll attend, but due to various unpredictabilities in my family, I can't plan that far ahead. I don't yet know whether anyone from Percona can attend, but I know a couple of our European consultants are looking at it and tossing around various proposals. (BTW, any lack of proposals / sessions from Percona is strictly our fault, in case there is concern about that. One person noticed and said something to me, so I thought it's worth mentioning.)

I'm thrilled that people thought the first OpenSQL Camp was valuable enough that they're carrying it …

There's a persistent perception that open source software is being ignored in the enterprise, that IT management fears it and it ends up being more costly to deploy than proprietary solutions. That's certainly the perception that some major software vendors would like you to have. But it's Jeffrey Hammond's job to dispel those perceptions, at least when they aren't accurate. As an analyst for Forrester Research, Hammond covers the world of software development as well as Web 2.0 and rich internet applications, so he sees how open source is being used on a daily basis. He'll be speaking at OSCON, the O'Reilly Open Source Convention, talking about the true cost of using open source, and he gave us a sample of what's going on in the enterprise at the moment.

James Turner: To begin, can you just talk about the areas you …

Today, I would like to introduce “skyload“, a small project that I’ve been working on for the last couple of weeks. In brief, skyload is a libdrizzle based load emulation tool that is capable of running concurrent load tests against database instances that can speak Drizzle (and/or) the MySQL protocol.

• http://code.google.com/p/skyload/

Something I’d like to emphasize here is that, skyload is not a replacement for mysqlslap or drizzleslap since it only provides a subset of what they can do. As I’ve stated on the project description, skyload is designed to do a good …

Video for the presentation at the 2009 MySQL Camp:
Chasing Bottlenecks
by Morgan Tocker

Description:
The best way to performance tune a system is to find out what your bottlenecks are, and attacking those first. In the first part of this session, I'll be looking at some of the issues faced with common database workloads. From there, I'll then be showing how you can get more information out of MySQL and your Operating System to find out about your workload. This session is designed for beginner to intermediate MySQL users.

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As The Clash reminded us, Know Your Rights!

A good friend whom I trust implicitly recently told me of a disturbing conversation that had taken place between a DBA acquaintance friend of his and a Sun sales engineer. Disturbing enough that it prompts me to remind everyone what your rights and obligations are when you use the community edition of MySQL that is licensed under the GPLv2.

Apparently, this friend of a friend needed some performance tuning done on a MySQL Community Edition installation that spans several servers, and serves up their proprietary, commercial web application. They contacted Sun in order to see …

I’ve started work on a c++ version of the Kontrollbase client script but am not as experienced in c++ as I’d like to be and don’t have the time to learn more c++ at the moment. The idea being that the client script written in perl has a lot of module dependencies and that complicates rolling out the client to large server farms. A compiled C++ script will be a drop-in solution.

So, if someone that is talented with c++ on Linux wants to help out the project and write a quick script involving a connection to mysql to run queries, and then connect to SNMP to gather system information, then export all of that to stdout as XML… let me know! I already have the MySQL part outputting XML so we just need the SNMP part and some error checking. Email me at themattreid at gmail dot com or commetnt on this post if interested. You’ll get credit on the project as a contributor.

On April 9-10 the National Science Foundation hosted the Workshop on the Science of Power Management (SciPM 2009), where I gave an invited talk. Here I give a brief summary of my talk along with a pointer to the slides.

The talk describes how MySQL with TokuDB can provide a path to more energy-efficient database implementations. It’s a theoretical talk. That is, rather than presenting results from an existing implementation, it provides food for thought about future possibilities.

Here’s an executive summary of the talk.

Disks use a substantial fraction of the computing power in a typical database application. Although different workloads and configurations can give very different values, somewhere around 1/3 to 2/3 of the total energy consumed by the computing unit seems like a good …