The half million
Gigabytes of data in the BABAR database, printed out, would
fill one billion books. That's nearly 60 times the number of
books in the Library of Congress, the largest library in the
world. "The need to store the avalanche of information coming
from the experiment and then efficiently search and retrieve
specific data samples has driven physicists and computer
experts to create innovative technology," said SLAC Director
Jonathan Dorfan. "Governments, commercial corporations and
institutes will face similar needs in the near future and the
knowledge and experience we have gained will be passed
on."
 Storing
and retrieving enormous amounts of data
In 1996, while
work was beginning on the construction of the experimental
apparatus, a small group of dedicated researchers at SLAC and
the Lawrence Berkeley National
Laboratory (LBNL), both U.S. Department of Energy
laboratories, began the arduous task of constructing an
efficient and convenient way of storing and retrieving the
enormous output of information expected from the experiment.
Working closely with physicists from the BABAR project, as
well as researchers at other physics laboratories, the
development team chose to base the system on a new
object-oriented database technology. Objectivity/DB, a product
of Objectivity, Inc.
based in nearby Mountain View in the
heart of Silicon Valley, was chosen to meet the demands of the
BABAR
data.
The team at SLAC
and LBNL worked over two years to customize the core database
software to provide the scientists with the initial features
they needed for this immense project. The SLAC and LBNL
researchers wrote more than half a million lines of software
code to provide the physicists access to their data in a
simple and reliable fashion. "We like the challenge", said
Jacek Becla, the BABAR Database group manager. "We bet on a
promising, but somewhat unproven, object-oriented database
technology back in 1996."
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In May 1999, the experiment began
taking data and the database was put to the test. It was not
at all clear that the technology could keep up with the vast
flow of information coming from the experiment. Bottlenecks
were found not only in the database software, but also in
other parts of the information system: the network used to
transmit the data, and even the operating systems of the
computers being used. One by one these problems were
eliminated and the database began to hit its stride. Now in
2002, the database is capable of recording data at speeds no
one had dared dream in 1999. More than a 1000 Gigabytes of
data can be stored every day.
A
good example of collaboration
"This milestone of 500,000 Gigabytes
is a vindication of the potential of object databases that we
anticipated when we embarked on this project," said LBNL's
David Quarrie, a chief architect of the system. "A lot of
credit should go to the members of the BABAR database group
and to Objectivity who have collaborated well with us. This is
a great example of how research scientists can collaborate
with high-tech industry to create new systems that in the near
future can benefit all kinds of fields."
Particle physics laboratories such
as SLAC have been leaders in information technology research
for decades. Ten years ago, SLAC researchers set the World
Wide Web loose on America, with astounding results. "We have
to stay on the cutting edge in order to use our resources in
the most efficient way", said Richard Mount, SLAC's Head of
Computing. "The database is the biggest not because we want it
to be but because we need it. And it looks like we have a lot
more scaling to do in the next few years as the amount of data
along with the number of data analysis jobs grows."
For more information about SLAC, the
BABAR Collaboration, and the BABAR database visit here.
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