Hi,
I have a weird question, but humor me please.
Is there anything, absolutely anything that a 3.2GHZ P4 with HT will do
better then a Core duo 2.16GHZ?
A long stream of simple addition in a single-threaded process....
Apologies if this is patronising, but it's helped alot of people I've
explained this to get the gist of what dual processing is all about.
Think of the two CPUs as dumper trucks. The Core Duo is equivalent to
two dumper trucks since it has two cores, the P4 as a single truck. All
the trucks have equal load bays. The P4 dumper truck can drive roughly
1/3 faster than both of the other two.
The work the processors need to do is move piles of sand from one place
to another. Humour me, this is going somewhere! Each truck has to have
its own pile of sand to move.
In the case where there is only one pile of sand to move, the Core Duo
dumper trucks can't share the work so one of them has to sit idle while
the other one moves the sand. Since it is slower by 1/3 than the P4
dumper truck it takes the Core Duo longer to move its pile of sand. This
is like having a single threaded process. It can only be executed on one
core at once and so can only be run at the speed of any individual core.
Now consider the instance where there are two piles of sand to move. The
Core Duo trucks can take a pile each whereas the P4 truck has to do
both piles itself. Therefore even through the P4 is faster to move each
load, it has to move more loads than each of the two Core Duo trucks
(which therefore finish faster). This is like having two processing
running simultaneously, or a single process that is written in such a
way that it can run different bits of itself in different threads (piles
of sand) and hence can take advantage of both cores at once.
Phew.
Alex
