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
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.
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
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
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 gridfactory.nbi.dk
- Import the app “ttbar_exercise”
- Select the application/dataset “ttbar_exercise-100k-events” and click “Run”
- Select the application/dataset “ttbar_exercise-merge” and
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
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
When my family and I recently moved into our new apartment, it was equipped with a front door with two locks: both of them with a spring latch. To get in, we needed to put a key in each and turn both while somehow turning the door handle at the same time. It could take quite a while … 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
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:
- GridFactory server
- The GridFactory server is the software running on the server to which jobs are submitted. It
– 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
Dear grid warriors: new tools are now available to assist you in your battles. The GridFactory software suite, including GridPilot, is now available for download.
GridPilot and GridWorker have been tested on the following platforms:
- Ubuntu 9.0.4, 9.10, 10.0.4 – i386
- Windows XP i386, Windows Vista i386 and Windows 7 i386 and x86_64
- Mac OS X 10.6
In this post I’ll report on running the application “mc09_7TeV.107691….” from the GridPilot app store. In the case of NorduGrid and WLCG, the ATLAS software is preinstalled on the resources. In the case of GridFactory, the jobs run inside a CernVM appliance with ATLAS software loaded through the AFS network file system. The input dataset consisted of 26 files totaling … Read the rest
In previous posts we saw that I/O bound jobs ran ~3 faster on standard SATA disks than on network file systems and block devices (GPFS, NFS, EBS). This post reports on CPU bound jobs. I ran standard ATLAS Monte Carlo simulation on both grid and cloud resources: imported the ATLAS simulation app and ran the default 100 small jobs, each … Read the rest
In this post, I’ll take a look at some more runs of the “atlas_d3pd_boildown” application available in the GridPilot app store. The difference w.r.t. the runs described in a previous post is that this time I ran on cloud as opposed to grid resources. On dedicated hardware and on two public clouds, Amazon’s EC2 and Cabo’s Irigo cloud, I … Read the rest
Professionally, I recently had to set up some improvised storage, making use of 6 machines, each with a 1 TB disk that was not used for anything else. Preferably with a common name space. Pooling such 6 disks into a common storage solution may sound like a common, mundane task, but there does not appear to be any open-source … Read the rest
In this post, I’ll take a look at some runs of the POV-Ray application available in the GridPilot app store: To import this app, just choose “File → Import application”, navigate to the relevant folder and click “OK”.
This example is special in that it does not depend on any preinstalled software package (runtime environment), but includes a precompiled binary. This binary will of course only for certain run on the system it was compiled on. We compiled on Debian Sarge and Scientific Linux 5 and run on all back-ends: a local virtual machine, GridFactory without virtualization and … Read the rest
Here is a video I put together to demo how to use GridPilot to run computations on a GridFactory cluster:
The demo uses the default input files – which are 12 royalty free music files found on incompetech.com. This can be changed – by right-clicking on the input dataset, “music_files”, and choosing “Import file(s)”. If you’ve already imported the … Read the rest
Given the popularity of the iPhone, an interesting use of a batch system is conversion of movie files from the AVI to the MPG4 format. In this post I’ll explain 3 ways doing this with GridPilot. Which way you prefer will likely depend on the number and size of files you want to convert and the power … Read the rest