Speaker
Marcin Plociennik
(PSNC)
Description
Due to the dynamic and complex nature of the Grid, it’s not
easy to use it in a daily
work. To attract new users, especially from scientific
community, user friendly tools
are needed to simplify access to the Grid. To solve this
problem we introduce the
concept of Migrating Desktop Platform which is a graphical,
user oriented product
that simplifies the use of the grid technology in the
application area.
Migrating Desktop Platform (MD) is an advanced graphical
user interface and a set of
tools combined with user-friendly outlook, similar to window
based operating systems.
It hides the complexity of the grid middleware and allows to
access grid resources in
an easy and transparent way with focus on interactive and
parallel grid applications.
These applications are both compute- and data-intensive and
are characterized by the
interaction with a person in a processing loop. MD can
attract new users by its
features: easy to use, platform independent, accessible from
anywhere, enables
possibility to easily add new application that can be batch
or interactive,
sequential or parallel. Thanks to its open architecture it
can easily integrate
existing or incoming tools - for example supporting grid
operations or enabling
collaborative work. Number of grid applications has already
been integrated with MD
framework.
As a key product of CrossGrid project Migrating Desktop has
proved its usefulness in
everyday work of users’ community. Migrating Desktop was
used in Polish grid project
– Progress and is now used as an integration platform in EU
BalticGrid project.
Interactivity and MPI support is also continually developed
in EU int.eu.grid
project, while tools from MD will become part of Eclipse
based grid toolbox developed
by EU g Eclipse project.
Platform overview
The aim of Migrating Desktop is to provide scientists with a
framework which hides
the details of most of the Grid services and allows working
with grid application in
an easy and transparent way. The graphical user interface
integrates and makes use of
number of middleware and integrates the individual tools
into a single product
providing a complete grid front-end. It uses OSGi
specification as a mechanism for
discovering, integrating, and running modules called
bundles. When MD is launched,
the users can work with environment composed of the set of
bundles. Usually a small
tool is written as a single bundle, whereas a complex tool
has its functionality
split across several bundles. A bundle is the smallest unit
of our platform that can
be developed and delivered separately. Such approach allows
increasing the
functionality in an easy way without the need of
architecture changes.
Migrating Desktop framework allows users to access
transparently the Grid resources,
run sequential or interactive, batch or MPI applications, to
monitor and visualize
applications, and manage data files. MD provides a front-end
framework for embedding
some of the application mechanisms and interfaces, and
allows the user to have
virtual access to Grid resources from other computational
nodes.
MD is a front end to Roaming Access Server (RAS), which
intermediates to
communication with different grid middleware and
applications. Roaming Access Server
offers a well-defined set of web-services that can be used
as an interface for
accessing HPC systems and services (based on various
technologies) in a common and
standardized way. All the communication is based on the web
services technology.
This platform can work with different grid testbeds: based
on LCG 2.7, gLite 3.0,
Progress 1.0. Due to its open nature it can be extended with
support for other testbeds.
Applications:
Example application use case: interactive application
(CrossGrid) - Parallel ANN
training application.
This application is used to train an Artificial Neural
Network (ANN) using simulated
data for the DELPHI experiment. The ANN is trained to
distinguish between signal
(Higgs bosson) events and background event (in the demo the
background used includes
WW and QCD events). The evolution of the training can be
monitored using MD with a
graphics presenting current error, and 4 small graphics that
show the ANN value vs.
an event variable (that can be selected by the user). The
application is compiled
with MPICH-P4 for intracluster use and with MPICH-G2 for
intercluster use. This
application uses the interactive input channel to let the
user make a clean stop of
the training (instead of killing the job), and also the
possibility of resetting the
ANN weights to random values, to avoid local minima. Using
MD, user can change
parameters of this grid application while it is running.
Other application that are already working with MD are: Air
Pollution (crossgrid),
Medical (Grid-based Approach for Virtual Arteries,
crossgrid), Flood Management
Applications (crossgrid), Air Pollution Modeling
(crossgrid), simple Magic
application use-case,
Planned in the nearest future are: Visualization of Plasma
in Fusion Reactors, GAMESS.
Used technology
Migrating Desktop bases on the Java applet technology. It
can be launched using the
Java Webstart technology or using a web browser with the
appropriate Java Plug-in
included in the Java Runtime Environment (JRE). MD is based
on Swing libraries for
designing graphical user interface, Java CoG Kit version 1.2
is being used as an
interface to Globus (for operation on proxy and GridFTP/FTP)
functionality. Axis
ver.1.2.1 web services client is used for communication with
the Roaming Access
Server. Migrating Desktop follows OSGi Service Platform
specification version 4
(August 2005) and is based on the same plugin engine as
Eclipse platform. Currently
RAS for cooperation with EGEE infrastructure is using LCG2.7
and/or gLite 3.0 platform.
Primary authors
Marcin Plociennik
(PSNC)
Norbert Meyer
(PSNC)
Pawel Wolniewicz
(PSNC)
