The Case for a Hierarchical System Model for Linux Clusters

The
computer
industry
today
is
no
longer
driven,
as
it
was
in
the
40s,
50s
and
60s,
by
High‐performance
 computing
requirements.

Rather,
HPC
systems,
especially
Leadership
class
systems,
sit
on
top
of
a
 pyramid
investment
mode.

Figure
1
shows
a
representative
pyramid
investment
model
for
systems
 hardware.

At
the
base
of
the
pyramid
is
the
huge
investment
(order
10s
of
Billions
of
US
Dollars
per
 year)
in
semiconductor
fabrication
and
process
technologies.
These
costs,
which
are
approximately
 doubling
with
every
generation,
are
funded
from
investments
multiple
markets:
enterprise,
desktops,
 games,
embedded
and
specialized
devices.
Over
and
above
these
base
technology
investments
are
 investments
for
critical
technology
elements
such
as
microprocessor,
chipsets
and
memory
ASIC
 components.
Investments
for
these
components
are
spread
across
the
same
markets
as
the
base
 semiconductor
processes
investments.

These
second
tier
investments
are
approximately
half
the
size
of
 the
lower
level
of
the
pyramid.
The
next
technology
investment
layer
up,
tier
3,
is
more
focused
on
 scalable
computing
systems
such
as
those
needed
for
HPC
and
other
markets.

These
tier
3
technology
 elements
include
networking
(SAN,
WAN
and
LAN),
interconnects
and
large
scalable
SMP
designs.

 Above
these
is
tier
4
are
relatively
small
investments
necessary
to
build
very
large,
scalable
systems
 high‐end
or
Leadership
class
systems.
Primary
among
these
are
the
specialized
network
designs
of
 vertically
integrated
systems,
etc.