Lenz Grimmer's blog

Last week, my colleagues Giuseppe, Kai and myself attended the SAPO Codebits event in Lisbon, Portugal. Codebits is an annual, invite-only hacking event, which went on for three days. The venue they chose this year was the "Cordoaria", a former rope factory located in the Belém district, close to the 25 de Abril Bridge (which is an impressive sight!). I have been told that the Cordoaria is the longest building in Portugal and I have no doubts about that! The building is so long that the crew used bicycles to get from one end to the other. I've taken a number of pictures from the event as well as from Lisbon itself, you can find them in this flickr set.

The organizers described this year's event as follows:

3 days. 24 hours a day. 600 attendees. Talks. Workshops. Lots of food and beverages. 24 hour programming/hacking competition. Quizz Show. Rock Band Contest. Lots of gaming consoles. More food. More beverages. More coding. Sleeping areas. More fun. An unforgettable experience.

I wholeheartedly agree, we had a great time! The conference started with sessions and presentations on a wide range of topics on the first two days. Afterwards, a 24-hour programming contest was held. I was invited to give two talks, one being my all-time favourite about "MySQL High Availability solutions" (slides, video), the other one was titled "Why you should be using a distributed version control system (DVCS) for your project" (video, slides). Both went quite well and the feedback I received was pretty positive. Giuseppe talked about "MySQL Schema Migration" (slides, video) and gave an "Introduction to Gearman" (video). Kai's talk was titled "Think before you develop" (video) and gave a nice roundup of tips and best practices for setting up and developing new web projects.

The Codebits session schedule was filled with amazing and interesting talks in four parallel tracks. Sometimes it was hard to choose – some other talks I attended and enjoyed:

• Robert Nyman: JavaScript - From Birth To Closure (slides, video)
• Glenn Jones: Re-using social media data (slides)
• Brian LeRoux: PhoneGap: Mobile App Developer Zero to Hero (video)
• Brian LeRoux: The State of JavaScript on Mobile Devices
• Walter Belgers: Becoming a lockpicker

Walter gave a lockpicking workshop after his presentation, which I attended as well. I was quite impressed (and a bit shocked) to find out how easy many locks can be opened this way! Later that evening there even was a live band named "Pornophonique" playing (one guy with a guitar, the other one using an Nintendo Game Boy for making music), but I missed that show as I was too busy opening more locks... Fortunately the concert and most of the sessions were recorded on video (in excellent quality) and are already available from the SAPO video pages. Kudos for this speedy service!

But this just matches my overall conclusion of this event: very well organized, great speakers and venue. Thanks to the organizers for having us, we really enjoyed our stay!

This blog post is a by-product of my preparation work for an upcoming talk titled "Why you should be using a distributed version control system (DVCS) for your project" at SAPO Codebits in Lisbon (December 3-5, 2009). Publishing these thoughts prior to the conference serves two purposes: getting some peer review on my findings and acting as a teaser for the actual talk. So please let me know — did I cover the relevant aspects or did I miss anything? What's your take on DVCS vs. the centralized approach? Why do you prefer one over the other? I'm looking forward to your comments!

Even though there are several distributed alternatives available for some years now (with Bazaar, git and Mercurial being the most prominent representatives here), many large and popular Open Source projects still use centralized systems like Subversion or even CVS to maintain their source code. While Subversion has eased some of the pains of CVS (e.g. better remote access, renaming/moving of files and directories, easy branching), the centralized approach by itself poses some disadvantages compared to distributed systems. So what are these? Let me give you a few examples of the limitations that a centralized system like Subversion has and how these affect the possible workflows and development practices.

This time of the year is usually a very busy one, as there are plenty of events and conferences to attend. Just take a look at our calendar of OSS events on the MySQL Forge to see what I mean! Here's a quick summary of the ones that I will attend and speak at until the end of this year:

On November 14-15, I'll attend the openSQL Camp in Portland (OR), USA. I missed the first one that took place in Charlottesville (VA) in 2008, but had a lot of fun organizing the European Edition earlier this year. The upcoming one will be more like an unconference again - the list of proposed sessions looks very interesting and the attendee list reads like a "who is who" list of the OSS database community.

On December 3-5, I'll be joining Giuseppe at SAPO Codebits in Lisbon, Portugal, which is going to be a very cool event: "3 days. 24 hours a day. 600 attendees. Talks. Workshops. Lots of food and beverages. 24 hour programming/hacking competition. Quizz Show. Rock Band Contest. Lots of gaming consoles. More food. More beverages. More coding. Sleeping areas. More fun. An unforgettable experience". I will be talking about my favorite topic of MySQL High Availability (I'm currently working on revising my slides based on several excellent discussions about MySQL HA that happened on Planet MySQL in the past weeks) and about the benefits (both social and technical) of using a distributed revision control system (DVCS) like bazaar, git or mercurial for your open source project.

Shortly after Codebits, I will attend SLAC 09, the "Secure Linux Administration Conference" in Berlin, Germany (December 10-11), where I will give two MySQL-related talks (in German) - my usual suspects, but in revised and extended form: MySQL High Availability solutions and MySQL Backup & Security best practices.

While Colin beat me in blogging about Project Kenai, I think I can still provide some additional background information about this new project hosting service from Sun.

If you are a maintainer of an Open Source project, you currently have plenty of choice when it comes to getting your project hosted for free. One criterion could be your software configuration management system (SCM) of choice.

Some of the hosting services that I am currently aware of and the choice of SCM they offer include:

• BitBucket (Mercurial)
• Collab.net (Subversion)
• github (Git)
• GoogleCode (Subversion)
• Launchpad (Bazaar)
• Sourceforge.net (CVS, Subversion)

As disclosed by Tim Bray some days ago, there now is another option - Kenai is open for project hosting (currently by invitation only)! In his blog post, he interviews Nick Sieger, one of the developers behind this project about their motivation and intentions:

We need to demonstrate credibility in building on top of more traditional LAMP/SAMP web stacks (not just Java EE); and we need to show viability of Sun technologies and hardware for next-generation web applications.

In a nutshell, Kenai is a platform for:

• Developer collaboration
• Communities of connected developers
• Integrated collaboration services stack

Some of the features that are currently available include:

• SCM services using Subversion and Mercurial
• Bug Tracking (Bugzilla)
• Forums
• Wikis
• Mailing Lists (using Sympa)

Reading the interview with Nick and looking at some presentations slides for RailsConf from Fernando Castano (a jRuby and Database performance engineer at Sun and another member of the project team),  I was able to gather a list of the tools and technologies they used to build Kenai:

• Apache2, mod_proxy_balancer
• Ruby on Rails (running on jRuby)
• Glassfish Java application server
• MySQL 5.0
• Apache Solr for search
• memcached

I found it interesting that they decided to deploy and run the Rails application as a war file within the Glassfish application server (using Warbler). By the way, the fabolous OpenSUSE Build Service is a Rails application, too! So far, the entire site is powered by a single MySQL instance with query cache enabled.

The project is hosted on the following infrastructure:

• Sun Fire T2000 for (for web and application serving)
• Sun Fire X4500 for Storage
• OpenSolaris Nevada (Zones/Containers, SMF)
• ZFS (9.7 TB RAIDz, Snapshots, NFS)
• Coolstack & Blastwave packages

You should check out Fernando's presentation for more technical details, tuning info and how they benchmarked the setup - it contains a number of useful tuning hints and performance graphs.

Last time I checked, 27 Projects have joined so far (e.g. jRuby, xVM Server). Kenai itself is developed on Kenai. It's going to be interesting what other projects will find their home there.

Nick also talked a bit about their future near term plans: to improve the usability and feature set, incrementally improve the site navigation and layout and adding support for hosting files/release downloads. They also consider offering Jira as an option to Bugzilla for bug tracking and Git as another SCM option.

There is an IRC channel #projectkenai on freenode.net, to get in touch with the developers directly. The mailing list for the Project Kenai site itself, is users@help.kenai.com - you can subscribe to this list here.