York Jong's Library tagged MIPS →  View Popular

Dividing memory
by speed defines a "time constant," roughly how
long it takes the computer to run once through its
memory. One megabyte per MIPS gives one second, a nice
human interval.

Machines with less memory for their
speed, typically new models, seem fast, but unnecessarily
limited to small programs. Models with more memory for
their speed, often ones reaching the end of their run,
can handle larger programs, but unpleasantly slowly.

Customers maintain the ratio by asking
"would the next dollar be better spent on more speed
or more memory?"

The megabyte/MIPS ratio seems to hold
for nervous systems too! The contingency is the other way
around: computers are configured to interact at human
time scales, and robots interacting with humans seem also
to be best at that ratio.

faster
machines, for instance audio and video processors and
controllers of high-performance aircraft, have many MIPS
for each megabyte. Very slow machines, for instance
time-lapse security cameras and automatic data libraries,
store many megabytes for each of their MIPS.

Flying
insects seem to be a few times faster than humans, so may
have more MIPS than megabytes. As in animals, cells in
plants signal one other electrochemically and
enzymatically. Some plant cells seem specialized for
communication, though apparently not as extremely as
animal neurons. One day we may find that plants remember
much, but process it slowly

With our conversions, a 100-MIPS robot, for instance
Navlab, has mental power similar to a 100,000-neuron
housefly. The following figure rates various entities.

MIPS and Megabytes.

Universal computers
can imitate other entities at their location in the
diagram, but the more specialized entities cannot. A
100-million-MIPS computer may be programmed not only to
think like a human, but also to imitate other
similarly-sized computers. But humans cannot imitate
100-million-MIPS computers--our general-purpose
calculation ability is under a millionth of a MIPS.

Computers doubled in capacity every two years after the war, a
pace that became an industry given: companies that wished to grow
sought to exceed it, companies that failed to keep up lost
business. In the 1980s the doubling time contracted to 18 months,
and computer performance in the late 1990s seems to be doubling
every 12 months.

Chip progress not only continued, it
sped up. Shorter-wavelength light was substituted, a more precise
way of implanting impurities was devised, voltages were reduced,
better insulators, shielding designs, more efficient transistor
designs, better heat sinks, denser pin patterns and
non-radioactive packaging materials were found. Where there is
sufficient financial incentive, there is a way. In fact,
solutions had been waiting in research labs for years, barely
noticed by the engineers in the field, who were perfecting
established processes, and worrying in print as those ran out of
steam. As the need became acute, enormous resources were
redirected to draft laboratory possibilities into production
realities.

The wave-like nature of matter at very small scales is a problem
for conventional transistors, which depend on the smooth flow of
masses of electrons. But, it is a property exploited by a radical
new class of components known as single-electron transistors and
quantum dots, which work by the interference of electron waves.
These new devices work better as they grow smaller. At the scale
of today's circuits, the interference patterns are so fine that
it takes only a little heat energy to bump electrons from crest
to crest, scrambling their operation. Thus, these circuits have
been demonstrated mostly at a few degrees above absolute zero.
But, as the devices are reduced, the interference patterns widen,
and it takes ever larger energy to disrupt them. Scaled to about
0.01 micrometers, quantum interference switching works at room
temperature.