347 research outputs found
The INFN-grid testbed
The Italian INFN-Grid Project is committed to set-up, run and manage an unprecedented nation-wide Grid infrastructure. The implementation and use of this INFN-Grid Testbed is presented and discussed. Particular care and attention are devoted to those activities, relevant for the management of the Testbed, carried out by the INFN within international Grid Projects
HEP Applications Evaluation of the EDG Testbed and Middleware
Workpackage 8 of the European Datagrid project was formed in January 2001
with representatives from the four LHC experiments, and with experiment
independent people from five of the six main EDG partners. In September 2002
WP8 was strengthened by the addition of effort from BaBar and D0. The original
mandate of WP8 was, following the definition of short- and long-term
requirements, to port experiment software to the EDG middleware and testbed
environment. A major additional activity has been testing the basic
functionality and performance of this environment. This paper reviews
experiences and evaluations in the areas of job submission, data management,
mass storage handling, information systems and monitoring. It also comments on
the problems of remote debugging, the portability of code, and scaling problems
with increasing numbers of jobs, sites and nodes. Reference is made to the
pioneeering work of Atlas and CMS in integrating the use of the EDG Testbed
into their data challenges. A forward look is made to essential software
developments within EDG and to the necessary cooperation between EDG and LCG
for the LCG prototype due in mid 2003.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
Conference (CHEP03), La Jolla, CA, USA, March 2003, 7 pages. PSN THCT00
Multi-core job submission and grid resource scheduling for ATLAS AthenaMP
AthenaMP is the multi-core implementation of the ATLAS software framework and allows the efficient sharing of memory pages between multiple threads of execution. This has now been validated for production and delivers a significant reduction on the overall application memory footprint with negligible CPU overhead. Before AthenaMP can be routinely run on the LHC Computing Grid it must be determined how the computing resources available to ATLAS can best exploit the notable improvements delivered by switching to this multi-process model. A study into the effectiveness and scalability of AthenaMP in a production environment will be presented. Best practices for configuring the main LRMS implementations currently used by grid sites will be identified in the context of multi-core scheduling optimisation
The Brain on Low Power Architectures - Efficient Simulation of Cortical Slow Waves and Asynchronous States
Efficient brain simulation is a scientific grand challenge, a
parallel/distributed coding challenge and a source of requirements and
suggestions for future computing architectures. Indeed, the human brain
includes about 10^15 synapses and 10^11 neurons activated at a mean rate of
several Hz. Full brain simulation poses Exascale challenges even if simulated
at the highest abstraction level. The WaveScalES experiment in the Human Brain
Project (HBP) has the goal of matching experimental measures and simulations of
slow waves during deep-sleep and anesthesia and the transition to other brain
states. The focus is the development of dedicated large-scale
parallel/distributed simulation technologies. The ExaNeSt project designs an
ARM-based, low-power HPC architecture scalable to million of cores, developing
a dedicated scalable interconnect system, and SWA/AW simulations are included
among the driving benchmarks. At the joint between both projects is the INFN
proprietary Distributed and Plastic Spiking Neural Networks (DPSNN) simulation
engine. DPSNN can be configured to stress either the networking or the
computation features available on the execution platforms. The simulation
stresses the networking component when the neural net - composed by a
relatively low number of neurons, each one projecting thousands of synapses -
is distributed over a large number of hardware cores. When growing the number
of neurons per core, the computation starts to be the dominating component for
short range connections. This paper reports about preliminary performance
results obtained on an ARM-based HPC prototype developed in the framework of
the ExaNeSt project. Furthermore, a comparison is given of instantaneous power,
total energy consumption, execution time and energetic cost per synaptic event
of SWA/AW DPSNN simulations when executed on either ARM- or Intel-based server
platforms
EU DataGRID testbed management and support at CERN
In this paper we report on the first two years of running the CERN testbed
site for the EU DataGRID project. The site consists of about 120 dual-processor
PCs distributed over several testbeds used for different purposes: software
development, system integration, and application tests. Activities at the site
included test productions of MonteCarlo data for LHC experiments, tutorials and
demonstrations of GRID technologies, and support for individual users analysis.
This paper focuses on node installation and configuration techniques, service
management, user support in a gridified environment, and includes
considerations on scalability and security issues and comparisons with
"traditional" production systems, as seen from the administrator point of view.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 7 pages, LaTeX. PSN THCT00
ATLAS and CMS applications on the WorldGrid testbed
WorldGrid is an intercontinental testbed spanning Europe and the US
integrating architecturally different Grid implementations based on the Globus
toolkit. It has been developed in the context of the DataTAG and iVDGL
projects, and successfully demonstrated during the WorldGrid demos at IST2002
(Copenhagen) and SC2002 (Baltimore). Two HEP experiments, ATLAS and CMS,
successful exploited the WorldGrid testbed for executing jobs simulating the
response of their detectors to physics eve nts produced by real collisions
expected at the LHC accelerator starting from 2007. This data intensive
activity has been run since many years on local dedicated computing farms
consisting of hundreds of nodes and Terabytes of disk and tape storage. Within
the WorldGrid testbed, for the first time HEP simulation jobs were submitted
and run indifferently on US and European resources, despite of their underlying
different Grid implementations, and produced data which could be retrieved and
further analysed on the submitting machine, or simply stored on the remote
resources and registered on a Replica Catalogue which made them available to
the Grid for further processing. In this contribution we describe the job
submission from Europe for both ATLAS and CMS applications, performed through
the GENIUS portal operating on top of an EDG User Interface submitting to an
EDG Resource Broker, pointing out the chosen interoperability solutions which
made US and European resources equivalent from the applications point of view,
the data management in the WorldGrid environment, and the CMS specific
production tools which were interfaced to the GENIUS portal.Comment: Poster paper from the 2003 Computing in High Energy and Nuclear
Physics (CHEP03), La Jolla, Ca, USA, March 2003, 10 pages, PDF. PSN TUCP004;
added credit to funding agenc
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