Silicon Graphics is building an Altix supercomputer for
the National Center for Supercomputing Applications (NCSA) that
will run a single Linux operating system image across 1,024 Intel
Itanium 2 processors and 3TBytes of shared memory.
Rob Pennington, interim director of the NCSA said the new
machine will be very different from the existing machines at the
facility, which include several Linux cluster supercomputers. Until
now, the largest shared-memory supercomputer available to
scientists there was an IBM p690 machine with 12 32-processor
nodes.
With the new Altix machine, researchers will have far more
computing power for their work, which includes weather-data
analysis, simulations of black-hole collisions and other
large-scale events in the evolution of the universe.
Earlier cluster supercomputers at the NCSA used multiple images
of the Linux operating system - one for each node - along with
dedicated memory allocations for each CPU. What makes this system
more powerful for researchers is that all of the memory will be
available for the applications and calculations, helping to speed
and refine the work being done, Pennington said.
"The users get one memory image they have to deal with," he
said. "This makes programming much easier, and we expect it to give
better performance as well."
Initially, Pennington said, the system will use two images of
Linux - one per 512 processors - while it is being tested and
configured. Later, all 1,024 processors will address one image of
the SGI Advanced Linux operating system being used. That operating
system is based on Red Hat Enterprise Linux.
Dan Kusnetzky, an analyst at market research company IDC, said
the Altix system follows a path of innovation that SGI has offered
for years in the supercomputing market.
"SGI has often led the field in how many processors they could
run on one operating system," he said.
The system called Cobalt, is a symmetric multiprocessor machine
that will be connected to a 370TByte SGI InfiniteStorage
shared-file system, according to SGI. The storage will also be
accessible to the other supercomputers at the NCSA.
The construction of Cobalt began with the delivery of the
storage equipment last month, and the machine is expected to be
fully online by 1 March. It has a potential peak performance of
more than six trillion floating-point operations per second
(TFlops), which will bring the total computing power at NCSA to
more than 35 TFlops and disc storage to three-quarters of a
petabyte.
SGI uses a proprietary NUMAflex shared-memory architecture that
allows memory to be shared across multiple commodity processors and
SGI ProPack for Linux, an application package that allows Linux to
scale to larger requirements.
Todd R Weiss writes for Computerworld