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Skeptic Postulates For Parallel
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Skeptic Postulates For Parallel
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Amdahl's Law
Amdahl's law made it so
pessimistic
to build parallel computer systems.
Due to the
intrinsic limit
set on the performance improvement (speed) regardless of the number of processors used.
An interesting observation to make here is that according to Amdahl's law,
is
fixed
and
does not scale
with the problem size,
.
However, it has been
practically observed
that some
real parallel algorithms
have a fraction that is a
function of
.
Let us assume that
is a function of
such that
(
3
.
5
)
This is clearly in
contradiction
to Amdahl's law.
It is therefore
possible to achieve a linear speed-up factor
for large-sized problems, given that
a condition that has been practically observed.