High-Energy Physics Applications on the Grid - Grid Computing: Infrastructure, Service, and Applications - page 430

#
# Ganga example
# Submit 3 jobs, one local, one on batch, one to the grid
#
j=Job(backend=Interactive(),application=Executable())
j.application.exe="/bin/echo"
j.application.args=["Hello world"]
j.submit()
j2=j.copy() # make a copy of the last job
j2.backend=LSF(queue=?8nm?) # submit to LSF
j2.submit()
j3=j.copy()
j3.backend=LCG() # run on the Grid
j3.submit()
FIGURE 17.1 A simple example where the same job (“Hello world”) is submitted to the
local machine, a batch system (LSF), and the LCG grid.
jobs in between sessions. Manipulations include being able to submit, kill,
resubmit, copy, and delete jobs. The repository is updated by a monitoring
loop, which queries all used back ends for the status of the jobs and
updates the status or triggers actions based on the state transition. For
example, a job that changes into a completed state triggers the retrieval of
the registered outputs from the submission back end.
Figure 17.2 illustrates the very large user basis which has been built
around Ganga. It is important to note that around 25% of the user commu-
nity (over 50 regular users each month) comes from non-HEP communities.
As an example of the usage of Ganga outside ATLAS and LHCb, I use
an example from theoretical physics. Quantum chromodyamics (QCD)
describes the interaction of the constituents of the hadronic matter (quark