Preamble: On performance, workload and scalability:
MySQL has always been focused on OLTP workloads. In fact, both Percona Server and MySQL 5.5.7rc have numerous performance improvements which benefit workloads that have high concurrency. Typical OLTP workloads feature numerous clients (perhaps hundreds or thousands) each reading and writing small chunks of data. The recent improvements to MySQL make it scale better for this workload when more resources (such as additional CPUs) are added. By scaling better I mean that it is able to take advantage of all available resources in order to handle the workload. One reason that it works best for this workload is that a single query executes in a single thread. MySQL never takes advantage of more than a single CPU when aggregating data and fetching rows from the buffer pool, with respect to a single query, but it can run many queries at once.

There are …

Oracle is investing in MySQL and is hiring in several areas including consulting, sales and pre-sales. Here are some of our open MySQL positions:

Europe:

Senior Principal Consultants, English and German speakers - Any European location.

Senior …

Yesterday afternoon I returned from the SAPO CodeBits 2010 conference, which took place in Lisbon, Portugal. Just like the previous year, CodeBits has been a great conference to be at and I am grateful for having been selected for participation. Thursday, the first conference day was quite a busy one for me — I gave two presentations in a row:

• What's new in MySQL 5.5? (Slides)
• How to build you own Quadrocopter (Slides)

Afterwards, I also participated in a panel discussion about " …

Welcome to , the weekly news blog about blogs in the datasphere… As we kick off , our own shares a few of her weekly favorites:

Oracle:

Arup Nanda posted an excellent script on how to summarize backup information from the rman catalog. He also posted a tool for automatically purging time-based partitions.

Pythian’s resident Exadata expert, Marc Fielding posted links to the …

I wonder if this comes under “Code Style” or not…

Anyway, Monty and I finished getting Drizzle ready for adding “-Wframe-larger-than=32768″ as a standard compiler flag. This means that no function within the Drizzle source tree can use greater than 32kb stack – it’s a compiler warning – and with -Werror, it means that it’s a build error.

GCC is not perfect at detecting stack usage, but it’s pretty good.

Why have we done this?

Well, there is a little bit of recursion in the server… and we can craft queries to blow a small stack (not so good). On MacOS X, the default thread stack size is only 512kb. This gives not many frames if 32kb stack is a even remotely common.

I found some interesting places to throw a lot of things on the stack too – that would be rather far down on a …

Here at Recorded Future we use Chef for Configuration Management, and I am a complete newcomer to this. Chef is, like Puppet, built in Ruby, Ruby sure seems popular for Configuration Management things.

As for the so called "recipes", which is what Chef names a things used for installing some software package, such as MySQL, is really not complete in the case of MySQL at least, but that is really not a big deal. I actually am beginning to like Chef, there are many good points to it, although I can't escape the feeling that I am spending more time writing Ruby than actually installing stuff and getting MySQL running. But I beleive that this most a result of the fact that we are still a startup and do not yet have that many MySQL servers running.

I my opinion, and I can be pretty opinionated as you know, I think the one big thing with Chef that I do not like is Ruby. I have to admit I really have to work hard to get used …

This week I showed one of my customers our MyEnv. He was very interested in it and suggested to make it known in public. In fact MyEnv is available for download already several years...

But I did not have the heart yet to announce it more publicly because it was not end user ready at all. So I used the weekend to make it nicer, consolidated some of the code, dropped old stuff etc. Now I think it is acceptable to use for public but not perfect.

So what is MyEnv?

MyEnv is a set of scripts to run comfortably multiple MySQL/MariaDB databases on the same server. You can even run multiple databases with different binary versions.

It is more comfortable than mysqld_multi and provides more functionality.

When to use MyEnv?

MyEnv is useful when you have to install several MySQL databases on one machine. This has to be done typically when:

• you have to consolidate many databases from …

Today I will describe the setup of a Hadoop / HDSF multi-node cluster on Debian Lenny with a redundant Namenode using DRBD and Heartbeat, four Datanodes and Tasktracker, a Backup- Checkpointnode and Rack awareness.

Hadoop Cluster Setup on Debian Lenny purposes

This article descibes how to setup a hadoop (version 0.21.0) cluster on debian lenny (version 5.x). I will not describe how to use MapReduce.

general

Hadoop is a framework for distributed computing written in Java. The project includs the following subprojects:

• HDFS: A distributed file system
• MapReduce: A framework for distributed large data processing

list of references

• http://en.wikipedia.org/wiki/Hadoop
• http://hadoop.apache.org/
• …

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Included in the package, two Live Virtual Classes (LVCs) can jumpstart your training. With LVCs, you get the same expert instructor and content as classroom training without the need for expensive travel.

Then demonstrate your proficiency using the certification exam vouchers in the package to obtain two certifications.

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Check out …

First of all: mysqldump is not converting tables. It is something else. Here is the story:

One of my clients had a case when they were migrating to a new mysql server: they used mysqldump to export data from the old server (all InnoDB) and imported it to the new server. When finished, all the tables became MyISAM on the new server. So they asked me this question:
“Why mysqldump is converting my tables from InnoDB to MyISAM?”

First of all we made sure that the tables are InnoDB on the old server. It was true.
Second we run “show engines” on the new server:

+------------+---------+----------------------------------------------------------------+--------------+------+------------+
| Engine | Support | Comment | Transactions | XA | Savepoints |
+------------+---------+----------------------------------------------------------------+--------------+------+------------+
| …