(message (Hello 'Talal)
(you :wrote
n '(Fri, 20 Apr 2007 14:34:48 GMT))
(
TI> My PC has a Pentium 4 at 2.4 GHz. One of the newer Intel Processors is
TI> a Core 2 Duo, also at 2.4 GHz. I understand that Core 2 is a dual core
TI> processor. Yet computationally speaking, system responsiveness, is the
TI> Core 2 faster than the Pentium 4? Much faster?
core2 has better 'instruction per cycle' parameter for most tasks, it can be
better in this parameter as much as 2 times, so core 2 duo 2.4 GHz can work
as fast as 4.8 GHz Pentium 4 -- even for single core!
since it uses two cores, you can get even better speedups -- 4x times faster
that single core p4, or even more..
this is because pentium4 uses some weird NetBurst architecture with very
long pipeline (never models have 31 instruction pipeline). as long as it's
doing some predictable loop, it works fine -- for example, it works fine in
cryptography, some video processing, it might be almost on par with core2.
but on some workloads branching it not predictable, pipeline gots broken,
and no surprise it gots some slowdown.
for some Java computational tasks i've got speedup of about 4 times when
moved from 3.0 GHz Pentium4 (Prescott) to 2.1 GHz Core2 -- and this app used
only one core! it's not typical situation though, possibly Java did
something that p4 doesn't like at all
.
)
(With-best-regards '(Alex Mizrahi) :aka 'killer_storm)
"I am everything you want and I am everything you need")