Rubyforge

Action Profiler allows you to profile a single Rails action to determine what to optimize. You can use the Production Log Analyzer and action_grep to determine which actions you should profile and what arguments to use.

Information on the Production Log Analyzer can be found at:

rails-analyzer.rubyforge.org/pl_analyze

Action Profiler REQUIRES Ruby 1.8.3, even if you just use Ruby’s builtin profiler.

Action Profiler can use three profilers, Ruby’s builtin profiler class, Shugo Maeda’s Prof or Ryan Davis’ ZenProfile.

Shugo Maeda’s Prof: raa.ruby-lang.org/project/ruby-prof

Ryan Davis’ ZenProfile: rubyforge.org/frs/?group_id=712&release_id=2476

Gem Installation

 gem install action_profiler

How can I top last week’s prediction about Google’s shipping container data centers? By explaining a bit more about how the system came to be and how it will work.

In last week’s column I told how Google has been experimenting with portable data centers built in standard 40-foot shipping containers. The idea isn’t new and it isn’t even Google’s. As far as I can tell it came originally from Brewster Kahle of the Internet Archive, who wants to replicate the archive here and there around the world and figured that a shipping container filled with servers and disk drives might be the easiest way to do so. Not only is it truly plug-and-play, but it is also a heck of a lot cheaper from a bit-schlepping perspective. Carrying a petabyte data center by ship from California to Australia is the virtual equivalent of an OC-192 optical connection - the world’s most powerful SneakerNet.

I’ve just released a very early version of a bridge that allows Rails applications to run reports written by the java reporting tool DataVision.

DataVision supports ruby as a scripting language (via JRuby) so it seemed a good fit. I haven’t had a chance to get my head around releasing it as a gem, plugin, etc so right now it’s just a tar that you extract in the directory of the app you want to "reportify".

You can download and/or find out more at rdb.rubyforge.org

Enjoy!

There has been a lot of attention to the legal encumbrances in Microsoft’s new MS XML format. In this article we’ll look at the technical side, and try to show you how the design of these formats affect interoperability. After all, that is the purpose of open standards.

OpenDocument benefits from 5 years of development involving many experts from diverse backgrounds (Boeing, National Archives of Australia, Society for Biblical literature, etc.). It was written with the explicit purpose of being interoperable across different platforms. In contrast, MS XML has not gone through a peer-review process, and was written with only one product in mind. This difference shows in the design of the formats.

Groklaw link.

RiskJobs is a German Headhunting website for the Risk Management domain. Applicants can fill out their profiles (tree structures) and companies can search: e.g. we need an operational risk expert with 3 years of experience that also knows X, Y and Z.

This adds one more app, the ever growing RealWorldUsage wiki page.

Well, actually skiing is good, too .. but I need sun!

 > Word is worse than a hog. It's a blabbermouth. I was once sent a business
 > proposal in Word format. I don't have Word, and Microsoft's free reader
 > was two versions old and never updated. To read the letter, I used a hex
 > editor, finding many interesting tidbits, including the printer on his
 > system, scraps of other documents to other people that indicated shady if
 > not criminal dealings, and the directory -- "Used Cars" -- that the letter
 > to me was composed in. I declined his offer to cooperate.
 >
 > Much of Word's bloat is "empty", but that means whatever was in RAM at
 > Store time.
 >
 > Jerry

Ive been playing with Avi Bryants continuation-based web framework Seaside, which is written in Smalltalk. Wow. Thats all I can say. After some recent work with Rails, I had come to admire the cleanliness of the frameworkeven if, on occasion, I had some complaints about short-cuts taken that need not be necessary. Compared to Seaside, Rails seems to me to be a jalopy. Dont get me wrong, its a seriously pimped out jalopy, but the easy with which one can build interactivity and modify it on the fly with Seaside is mind-blowing.

…

NB: Dont take this as a slam of Rails, as its not. Rails is brilliantfor what it is. It takes the historical model of page interaction and data storage to new heights of simplicity. It doesnt, however, change how you view the web. Seaside does. Whether you use it for your next project, or not, its worth looking at, going through the tutorials, and allowing your mind to conceive of a web that simply behaves more naturally.

blog.amber.org/2005/11/23/she-sells-seashells-by-the-seaside/

With Seaside Avi wrote sth. interesting: dabbledb.com/about/.

I fid finally read this bestseller. As a big fan of genetic algorithms and swarm particle intelligence I simply loved the idea of the smart Yrrs. A fascinating book about intelligent aliens living on the ground of the sea who have enough of us human beings polluting the world. Highly recommended 900 pages of fun

Even when using a IDE it can be very handy to get into a irb session at any moment.

You need to install ruby-breakpoints

 require 'breakpoint'
 ..
 if m==0
    puts "m is 0"
    pp xs
    puts ys.to_yaml
    breakpoint
 end
 ..

Useful:

• use CTRL-D (Unix) or CTRL-Z (Windows) or exit to leave the breakpoint and continue running the program
• use exit! to terminate the program from within a breakpoint
• other interesting things to check out include: local_variables, instance_variables, caller, methods
• just type the name of your variable to check its value
• Note that you can enter any type of regular Ruby code into a breakpoint IRB shell. You can even hot patch your deployed code to fix a problem at run-time!

If you are developing a rails app, check out the wiki entry.

I take my break now. Off for yammie food.

www.xprogramming.com/xpmag/xstComplexScope.htm

  require 'audio/sndfile'

  Audio::Soundfile.open('chunky_bacon.wav') do |sf|
    sound = sf.readf_float(sf.frames)

    puts "Maximum amplitude: #{sound.abs.max}"

    sound.each_frame do |frame|
    # something cool
    end
  end

1. hans.fugal.net/src/ruby-audio/
2. www.mega-nerd.com/libsndfile/

The MIT Media Lab has launched a new research initiative to develop a $100 laptopa technology that could revolutionize how we educate the world’s children. To achieve this goal, a new, non-profit association, One Laptop per Child (OLPC), has been created. The initiative was first announced by Nicholas Negroponte, Lab chairman and co-founder, at the World Economic Forum at Davos, Switzerland in January 2005.

This rugged laptop will be WiFi-enabled and have USB ports galore. Its current specifications are: 500MHz, 1GB, 1 Megapixel.

laptop.media.mit.edu/laptop-images.html

I was looking for the rails offline documentation. In the end I did run rake over the latest rails code, but hey, I could have saved a bit of time. Maybe one day I should start to RTFM.

Download.

Synopsis: Imagine that you meet a very old man who—you eventually realize—knows literally everything. Imagine that he explains for you the great mysteries of life—quantum physics, evolution, God, gravity, light, psychic phenomenon, and probability—in a way so simple, so novel, and so compelling that it all fits together and makes perfect sense. What does it feel like to suddenly understand everything? God’s Debris isn’t the final answer to the Big Questions. But it might be the most compelling vision of reality you will ever read. The thought experiment is this: Try to figure out what’s wrong with the old man’s explanation of reality. Share the book with your smart friends then discuss it later while enjoying a beverage.

Scott Adams made it free to boost his hard to market book. I have not yet read it, but heard good reports.

Enjoy and help the project! Oh boy, I do feel young again :-).

It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagating the changes in each replica to the other.

Unison shares a number of features with tools such as configuration management packages (CVS, PRCS, Subversion, BitKeeper, etc.), distributed filesystems (Coda, etc.), uni-directional mirroring utilities (rsync, etc.), and other synchronizers (Intellisync, Reconcile, etc). However, there are several points where it differs:

• Unison runs on both Windows and many flavors of Unix (Solaris, Linux, OS X, etc.) systems. Moreover, Unison works across platforms, allowing you to synchronize a Windows laptop with a Unix server, for example.
• Unlike simple mirroring or backup utilities, Unison can deal with updates to both replicas of a distributed directory structure. Updates that do not conflict are propagated automatically. Conflicting updates are detected and displayed.
• Unlike a distributed filesystem, Unison is a user-level program: there is no need to modify the kernel or to have superuser privileges on either host.
• Unison works between any pair of machines connected to the internet, communicating over either a direct socket link or tunneling over an encrypted ssh connection. It is careful with network bandwidth, and runs well over slow links such as PPP connections. Transfers of small updates to large files are optimized using a compression protocol similar to rsync.
• Unison is resilient to failure. It is careful to leave the replicas and its own private structures in a sensible state at all times, even in case of abnormal termination or communication failures.
• Unison has a clear and precise specification.
• Unison is free; full source code is available under the GNU Public License.