Author Archives: frederik


Back in Barcelona to present a paper at 3PGCIC-2011 – a well organized and pleasant conference with a varied program. Good discussions on distributed computing. Excellent social arrangements including the reception banquet at the charming Institut d’Estudis Catalans and a visit to the Mare Nostrum supercomputer of the BSC – located in a former chapel.

.… Read the rest

Taking citizen cyberscience a step further

Citizen Science

Recently I’ve stumbled upon the terms citizen science and citizen cyberscience. The last term was apparently invented by Shuttleworth Fellow Francois Grey as a label for BOINC-based distributed computing projects like seti@home, folding@home and his own lhc@home. Grey is also behind the Citizen Cyberscience Centre in Geneva – on the web pages of which there’s more information to be … Read the rest

CERN School of Computing 2011 was… awesome


As exemplified on the pictures above (from the photo gallery of one of the students), CERN School of Computing includes a good deal of extracurricular activities. Which probably goes a long way in explaining the good and humorous atmosphere in the classroom.

Having spent a lot of energy preparing the exercise with the great CSC team, it really was great … Read the rest

The vision of GridFactory


In this post I’ll try to explain the vision behind a software suite I wrote at the Niels Bohr Institute, University of Copenhagen, 2009-11.

The ideas for the software arose from my dual involvement with the high energy physics and the e-science groups. Some of the code originated in previous projects, including distributed computing efforts of the ATLAS experiment at … Read the rest

Van der Pals

"Works for cello & piano" by Leopold van der Pals

Works for cello & piano by Leopold van der Pals

Came across this CD by chance. The soloist – living here on Østerbro, is the grandson of the composer .

Post-romantic, austerity, suspense and longing. Apparently it appeals to the younger generations :-)

Pablo (and tia Chata) enjoying the music:

To see the video → Read the rest

Headweb on Boxee Beta


I’m quite happy with my small HTPC running Boxee on Ubuntu. The hardware is a Zotac Ion board with an Atom CPU and an Nvidia graphics card. Both software and hardware have their issues, but after enough hacking I’ve a setup that gets the job done wrt. watching movies off my file server. My main gripe has been the lack … Read the rest

CERN School of Computing 2011 – Exercise 2

In this exercise we’ll solve the same assignment as in exercise 1, but using a prepackaged GridPilot application.

  • Download and install GridPilot
  • Start GridPilot and answer the initial questions – enable only the computing system “GridFactory” and set the submission host to
  • Import the app “ttbar_exercise”
  • Select the application/dataset “ttbar_exercise-100k-events” and click “Run”
  • Select the application/dataset “ttbar_exercise-merge” and
  • Read the rest

CERN School of Computing 2011 – Exercise 1

pT diboson distribution.

pT diboson distribution.

This exercise was created for the 2011 CERN CERN School of Computing, hosted by the Niels Bohr Institute, University of Copenhagen.

Credits: physics content of this exercise by Jørgen Beck Hansen from the Niels Bohr Institute.

LHC Monte Carlo event generation and analysis

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Since November 2010 we’re living on Østerbro – and very happy with the neighborhood. Kindergarten, shopping, swimming, karate, fitness and cafe’s all very close and very children friendly.

Here’s a picture of spring coming to our backyard:

IMG 0116


Browser certificate and key export

This is a follow-up post to my previous post “Front door locks”.

I’m happy to announce a little utility that exports TCS certificate/keys to the hard disk – more precisely to your “.globus” directory where grid tools expect to find them.

Here follows instructions on how to use it:

First, you of course need to have some TCS credentials … Read the rest


The original purpose of GridPilot was to make it easy for researchers to run, preserve, rerun, share computations on the emerging national and international grid infrastructures. The word infrastructure is used in plural here – indicating our failure to create the grid. Thus GridPilot was born with a pluggable backend support.

Eventually, I created my own take at a grid … Read the rest

GridFactory software suite – overview and documentation

In this post I’ll give an overview of the GridFactory software suite (including GridPilot) and provide the minimum information to get started as well as pointers to more thorough documentation.



GridFactory is a software suite composed of the following programs:

factory_c_smallGridFactory server
The GridFactory server is the software running on the server to which jobs are submitted. It

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GridFactory server installation instructions

Notice that currently the software has only been tested on Ubuntu-9.10, 10.04 and Fedora-12, 13 – i386*

Notice also that you must first install SUN/Oracle’s Java (=1.6), either from a distribution repository or directly from Oracle.

Download and installation on Ubuntu


Download mod_gacl, mod_gridfactory, gridfactory_server: either use your browser and get the files from

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