Am 14.06.2010 16:41, schrieb Invisible:

>> You cannot just take a mathematical paper and expect it to work as
>> described on a computer, you never have been able to.
>
> Back in the days of the 8-bit home computer, memory access really was a
> constant-time operation that always took 1 clock cycle. Unfortunately it
> seems that the larger a memory bank is, the slower it is to access. What
> this means is that a 2.2 GHz CPU only runs at 2.2 GHz if you use a tiny
> amount of data. If you try to random-access a large chunk of data,
> suddenly the program slows down to the speed of the RAM bus.

(1) Home computers were toys.

(2) Capacity of memory basically has nothing to do with access speed. 
The effect you describe for that 2.2 GHz CPU is the effects due to L1 
and L2 caches - which aren't faster because they are smaller, but 
because (a) they're closer to the CPU core and (b) they're using faster 
(but more space-consuming) technology.

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