Re: Version after Version

Now I've been long removed from the architecture of the machine, but isn't
it correct to say that with a 64 bit processor, we're talking about being
able to load the equivalent of two 32 bit words with a single clock cycle?
That would suggest that, although the clock speed is the same with the 32
and 64 bit processor (one not faster than the other), the latter would
process twice as many bits of data for each clock cycle. Thus this would
suggest that you can 'process' twice as much within a given time.

All that would be required is to write software that actually did this,
rather than load in only 16 or 32 bit words into a 64 bit and leaving the
other half unused (thus no gain in performance).

And consider how multi-threading would play into this. :-)





"Marc Rohloff" <marcrohloff_ng@xxxxxxxxxxx> wrote in message
news:1130333026.845256.215150@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>
> Frank de Groot wrote:
>
>> > While the move from 16 to 32 bit was of major significance, the
>> > emergence of 64 bit processors strikes me as something of a yawn.
>
>> Not if you need speed.
>> When written to take advantage of the 64-bit wide data path, applications
>> can become twice as fast.
>
> Not true.
> a) A 64 bit processor is not twice as fast as a 32 bit processor.
> b) Since pointers become wider data and code size will increase
> significantly requiring more RAM to perform the same task, more memory
> transfers and more processor cycles.
>
> --
> Marc
>


.

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