GlueX Computing GlueX Collaboration Meeting Glasgow

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GlueX ComputingGlueX Collaboration Meeting
Glasgow
Edward Brash University of Regina
August 4th, 2003
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Detector Simulations at University of Regina
Over the last year, we have been working on
developing tools for carrying out and managing
GlueX detector simulations (HDGeant)
- Development of a grid portal, to allow job
submission and monitoring from any web
browser. - Development of a relational database
to manage the simulation efforts. - Use of
grid certificates to allow secure access to
and management of resources. - Installation and
testing of SRM tools for transferring data
from JLab MSS to Regina (and vice versa).
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Security Certificates in Globus
- Each host computer generates a certificate
request, which is sent to a signing authority,
who returns a signed certificate for the host. -
Currently, we are using the gridcanada.ca signing
authority. However, there currently exist
utilities within the globus toolkit which allow
the generation of certificate requests for
multiple signing authorities. - Users generate
personal certificate requests, and these are also
signed by the certificate authority. This
certificate travels with you, and thus you can
use any computer to submit jobs, as long as it
has the globus client tools installed, and you
have installed your personal certificate. - Web
portals can work in a similar way, with a single
sign-on allowing access to multiple sets of
resources.
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Globus Installation at UofR
- Alpha computing cluster with 50 AlphaLinux
CPU's sitting on a VPN behind a Tru64 Unix
server. We run OpenPBS (www.openpbs.org) as the
batch job scheduler. - The Tru64 server runs
pbs server and a scheduler. The AlphaLinux
CPU's run a pbs client program. - In addition,
we have several other Redhat Linux PC's which
also run the pbs client program. - Installation
of Globus 2.0 Toolkit on the Tru64 Unix server
and on the Linux PC's was moderately
straightforward. - Included in the Globus
Toolkit are job managers for various
batch queueing systems, like Condor, OpenPBS,
etc. Some customization of the PBS job manager
was necessary to interface with our installation.

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PBS and Globus Job Submission
!/bin/sh cd /raid0/GlueX/ echo Running on
hostname cd sisyphus/debugging/test cd
omegadelta2_107567434/omegadelta290 pwd ./runsim
90 omegadelta2 50000 6 2 BV 0.2mm mv
omegadelta290.xml ../omegadelta290.xml mv
omegadelta290.hddm ../omegadelta290.hddm cd .. rm
-fr omegadelta290/
- With Globus, job scripts are just a regular
shell scripts. - This has the added advantage
that is can easily be run interactively for
testing purposes.
globus-job-submit vivace.phys.uregina.ca/job-man
ager-pbs -q verylong -x (jobtypesingle)
-np 1 -s myscript.sh
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GridPort Web Portal
- Web-based access to globus-job-submit,
globus-job-status, and globus-job-get-output
(and other globus) commands. - Series of perl
modules, cgi scripts, and php code running on a
secure web server. - Also allows single sign
on, using a local globus certificate for proxy
generation. - At UofR, we have a working portal
for both GlueX detector simulations, and for
Pion Form Factor simulations.
Https//www.phys.uregina.ca/GlueX/
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What Should A Simulation Resource Look Like?
- It should probably have the standard GlueX
software installed for all of the
architectures that comprise it - Event
generators (genr8, cwrap) - Translators
(ascii2stdhep, stdhep2ascii, hddm-xml, ...) -
Basic HDGeant parameter files (dsolenoid.table,
...) - Given that we want to test many
different geometries, the user should be able to
choose from a set of standard geometries, or
specify their own. For the latter, this means
provide your own HDGeant executable (for the
approp. architecture). - Given that we want to
simulate many different reactions, one should be
able to choose from a set of standard ones, as
well as specify their own. This means
providing the input file for your favourite event
generator. - If you do something interesting,
others should benefit immediately from it.