Tag Archives: Linux

Google Tech Talk : One Laptop Per Child

The aim of OLPC is to change how kids learn.

Ivan Krstic, Chief Security Architect at OLPC gives a technical talk on how the laptop was designed and how they are going about building it. He goes to great length to explain why they are doing this, the rationale behind the project, and why this influenced many of the technical decisions.

How do you build laptops for kids?

The Original XO-1 laptop has the following spec:

  • Geode GX-500 1.0W, 366Mhz,16kb L1, cache no L2
  • 128 MB RAM
  • 512 MB NAND Flash

The newer version has the following hardware spec:

  • AMD Geode LX-700 0.8W, 433Mhz, 128KB L1, 128KB L2.
  • 256 MB Ram
  • 1024 MB NAND flash

The laptop has no moving parts which helps keep the power usage down. It;s peak power consumption is 4-5W, the standard consumption is closer to 1-2W. Compare this to a normal conventional laptop which is around 40 – 50W. One of the things that stands our for me in this talk is that the OLPC team and doing what is probably the most aggressive work in Power Management using Linux anywhere in the world. In order to conserve more power they’re goal is to suspend the machine every 2 to 3 seconds if nothing on the screen is changing. They actually target they have set is to be able to suspend and resume the machine at the edge of human perception which is ~100ms. That’s incredible!

If you set aside the social aspects of this project and focus purely on the technical goals they’re attempting to achieve, the OLPC project could radically change the way laptops are built. It’s well worth watching the talk, there’s a number of other unique advancements the project has made, and I for one will be keeping a close eye on its development.

7 habits for effective text editing

Here’s a really cool talk by Bram Moolenaar the creator of Vim. There’ some really great tips some of which are obvious others aren’t. I remember when Rob and I were paired on Cenote, we did most of our development work on Fedora Core, Rob re-introduced my to Vi and Vim and gave me loads of great tips, this talk was somewhat reminiscent of that. It’s definitly worth watching!

Librarians stake their future on Open Source

Linux.com is running and article on how a group of librarians Georgia Public Library Service have developed an open source enterprise class library management system that has the potential to revolutionise the way large scale libraries are run.

You can read the article here.

The production system is code named Evergreen, and you can find out more about it here, and use the working system, here.

My first impression of it is that I like it, it’s simple to use and doesnt feel like an OPAC, like the hugely disappointing http://www.worldcat.org does.

Unfortunatly I can’t seem to login to the system with the demonstration username and passwords, but I am really interested in trying out the Shelf Browser feature.

OLPC – One Laptop Per Child Video Tour

Was very impressed when I saw how far the OLPC project had come, this demonstration of the user interface on this Linux based laptops is simple and intuitive and a world apart from the bare Linux interfaces most of us are used to. You can also learn about the history and some of the issues faced by the project on Wikipedia, as well as view official information at the OLPC Homepage. The laptops are will cost $100, and a represent an opportunity to revolutionise how we teach the worlds children – with an emphasis on developing nations where access to technology is limited for under privileged children.

Oh and did I mention that they are wind-up powered??

Platform dependent file-locking

MS Windows and Linux handle file locking differently. This article describes both approaches in detail. To summarise though, when you open a file for reading, under windows it prevents others from deleting it or writing to it, however under Linux it does not.

I fell foul of this while trying to run some Java based unit tests that worked perfectly well under Linux but started throwing errors on windows.

ThoughtPolice – VM Images for major OS’s

At Talis we’ve been doing a lot of work using vmware, I routinely run a Fedora Core 5 image for developing code in, which works wonderfully well on the dell laptop I have which has virtualisation support and lots of memory ;-) I also have Red Hat, KNOPPIX and SUSE VM machine for trying out other things.

One of my colleagues, Rob Styles, introduced me to thoughtpolice.co.uk, who have provided VM Images of many popular distros, this lowers the barrier hugely since I dont have to worry about installing a distro from scratch which can be time consuming. I use this site regularly and recommend that anyone who might be thinking of setting up a virtual machine running a linux distro to check here before installing from scratch.

http://www.thoughtpolice.co.uk/vmware

Buildix – KNOPPIX Based Linux Distro

Heard about this on a Google tech talk, its a linux distro distributed as an rpm or VM ( which I have downloaded ), it provides a pre configured install of CruiseControl, Trac and Subversion …

Martin Fowler mentions it on his site, obviously hes recommending it because of his involvement with thoughtworks. Nevertheless its a great idea, based around shortening iteration zero.

There’s a good blog by one of the “authors” describing why they made this, which is well worth reading.

I’ve found it easy to use and configure and it gives a great head start to project teams trying to get continuous integration environments set up.