Workshop on virtualization and multi-core technologies for LHC
(CERN), Predrag Buncic
(CERN), vincenzo innocente
Kickoff workshop for the new computing R&D projects to exploit the virtualization and multi-core technologies for the particle physics community. The idea is to bring together some of the technology vendors, the LHC collaborations and experts on the domain to share their experiences and needs in order to elaborate a possible program of work for the new R&D projects.
EVO Meeting available in "Universe" community.
It is also possible to phone in following this instructions http://evo.vrvs.org/evoGate/Documentation/EVO_Telephone_Bridge.pdf
Experience and plans on adapting software for multi-core
Introduction to the R&D project30m
ATLAS experiences running athena and TDAQ software30m
(High Energy Physics)
Experience in parallel programming using Python in LHCb30m
CMS experience and plans30m
First Results in a Thread-Parallel Geant430m
We have taken the TOP-C parallelization of Geant4 (based on MPI),
to semi-automatically create a thread-parallel Geant4 based on event
parallelism and a master-worker style of parallelism. We currently
address two issues:
1) detecting global variables and data structures, which must be
made thread-local. We modify the parser of the gcc compiler to
2) handling of random generator engines from CLHEP. This is needed to create
reproducible results by assigning known random seeds to each distinct thread.
The very preliminary tests show linear speedup with the number of cores,
up to the four cores of a quad-core processor. Future work will consider
moving some of the thread-local data back into process-global data,
in order to reduce the image size (eliminate separate copies per thread),
and to further ensure scalability for large experiments. We have also
demonstrated that our checkpointing package, DMTCP, works in this
thread-parallel environment operating in CERN 64-bit Scientific Linux.
Gene Cooperman, Xin Dong
(Northeastern University, Boston, USA)