¦ Images of Virtuality –Athens Particle Physics and Virtuality: a discussion on researching a virtual distributed community for the LHC at CERN. Dr. Will Venters Lecturer Information Systems and Innovation Group Department of Management The London School of Economics and Political Science This research was undertaken as part of Pegasus EPSRC: Grant No: EP/D049954/1

¦ Images of Virtuality –Athens Overview The socio-material nature of virtuality within a truly virtual domain: Particle Physics Grid infrastructure Tentative Research Question: How is the Grid shaped by the agency of users & SysAdmin? Theoretical Framework: Mangle of Practice Conclusion: Virtual vs. physical… User vs. Sysadmin

¦ Images of Virtuality –Athens EPS Conference on High Energy Physics, Manchester 23 July 2007

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¦ Images of Virtuality –Athens Data Deluge. ~100,000,000 channels, 600,000,000 collisions per second,. Searching for Higgs Boson – 1 person in 1000 worlds, or a needle in 20 million haystacks million gigabytes per year. 100k CPUs, 40PB disk, 40PB tape.

¦ Images of Virtuality –Athens CERNs computing hall – largest of 237 sites on the Grid.

¦ Images of Virtuality –Athens But what is a Grid? Coordinated resource sharing and problem solving in dynamic, multi-institutional virtual organizations " (Foster, 2001) … which enable disparate groups of organisations and/or individuals to share resources in a controlled fashion, so that members may collaborate to achieve a shared goal (Foster, 2001) Enable re-scaling of practice (Hey at al. 2002)

¦ Images of Virtuality –Athens Why Particle Physics? Elite science Tradition of global collaborations (Traweek 1988). Collaborative working practices (Knorr-Cetina 1999) Successful advanced ICT (Web, Cray, Open-Source, Server-farms). Advanced computer users.

¦ Images of Virtuality –Athens Theoretical Framework Andrew Pickering (1995,2009) – Mangle of Practice Performative ; Science as emergent interplay of human and material agency – reciprocally and temporally constituted (Pickering 1995) Responds to call to consider materiality of technology (Orlikowski 2001; 2007) but not reifying technology nor social practices. World is a lively place full of agency (Pickering 2002) Human Intentionality. The focal purpose – a relatively fixed image of some future state. Human and material agency are mutually and emergently productive of one another (Pickering1993) through a dialectic – the Mangle of Practice. But the Mangle does not respond to the collective well (Pinch 1999) Communities of Practice (Wenger 1998) as conceptual framework for the collective.

¦ Images of Virtuality –Athens Example Virtual Organisation: ~2300 globally distributed physicists working on the CMS experiment

¦ Images of Virtuality –Athens CoP – CMS Physicists Grid is: just a processing machine that sits there People want enough disk space, they want fast CPUs that they can run there usually very inefficient programmes on, and they want it 24/7 and during Christmas! Physicists are very dirty programmers… they usually want the fast hack. They will fly to CERN taking a stack of writable CDs and flying back to London… Only if you have a Grid at a workable level is it an alternative

¦ Images of Virtuality –Athens Running a CRAB job Workload Manager Middleware (part of Grid) reflects SysAdmin… CRAB ( C MS R emote A nalysis B uilder) Operating Crab (and LCG) within the CMS community : People learn…by getting a working script from someone… and starting from there and trying to run it and trying to modify it to suit there needs. Scripts are regularly ed to others to help with problems and provide advice. FAQs, documentation, Blogs and Wikis are used developed.

¦ Images of Virtuality –Athens Resistance & Accommodation Impossible to monitor what is going wrong Crab gets blamed… there is a school of thought that the last letter should be changed to P Unclear support: No local systems administrators. Crab creates a barrier… invariably the problems falls between [Grid and CMS]. So Grid people dont know what I am talking about… and CMS software people say its a Grid problem.

¦ Images of Virtuality –Athens Change in practice New work practices emerge Being a systems administrator for particle physics must be hell, they will want different systems for everything, and they are all quite savvy, they will tune everything…. Just kill problematic jobs which take too long to run Black-list and White-list feature for testing/management. #Ce_black_list=*.fnal.gov,*.ral.ac.uk #Se_black_list=*.fnal.gov,*.ral.ac.uk #Ce_white_list=*.cern.ch #Se_white_list=*.cern.ch

¦ Images of Virtuality –Athens Grids: coordinated resource sharing (Foster & Kesselman 1998). In practice the way I operate is; I find out where my data is and tell this Crab tool where to go. the only way it works is if you find out where the data is and they you tell the thing to send it there. Doing this releases more time to make [physics analysis] happen

¦ Images of Virtuality –Athens SysAdmin Experiments develop independent monitoring systems that report independently the situation of the infrastructure as they see it. Not as the managers see it. If there was a user sitting in isolation they would have to use what we provide…. But they all work for experiments with lots of influence and resources and everything. And which occasionally, possibly often, have very high influence in some of the sites as well, they can ask the sites to install various services. So they can bypass stuff. But workload management might be scrapped, because it would be investment in something useless

¦ Images of Virtuality –Athens Tentative contributions Battle of Intentionality of PP and SysAdmin as infrastructure is performed. Fundamental change in the Infrastructure… Not just Shaping/innovation Norms of behaviour – tinkering, bricolage, improvisation. Questions relationship between user and developer/maintainer (Woolgar) Cloud computing – Role of ICT in organisations?

¦ Images of Virtuality –Athens Will Venters;