48-bit computers ?

Skip to first unread message

Skybuck Flying

Feb 25, 2015, 11:52:35 AM2/25/15
Now that I am faced with the scenerios were 32 bits is not enough anymore,
the transition to 64 bit feels too expensive.

I worry/fear that most of the upper 32 bits of the 64 bit integers for
example will not be used and thus are populating the data caches and also
instruction caches.

Those caches are very important.

I think 48-bit computers might give 25% more performance than the same
64-bit computer.

Thus my questions are:

Did you guys consider creating 48-bit computers ?

Ofcourse the memory system would have to be 48-bit as well.. so that 48 bits
can be retrieved all at once for maximum efficiency.

And a 48-bit processor with 48-bit registers.

And finally 48-bit compilers.

I think eventually most programmers would probably be a little bit more
happy with that because it will make their software run faster.

For now die-shrinks and transitions to lower nanometers might be possible,
but perhaps in a few years that might seize to exist.

Thus perhaps a transition to 48-bit might have made more sense, and might
still make some sense.

Commercially it be more interesting for chip manufacturers...

48-bit computer will last about 20 years. While 64 bit computers will last
abour 35 to 40 years.

Selling 48 bit computers now would have allowed you to sell 64 bit computers
in the future.


Skybuck Flying

Feb 25, 2015, 7:53:24 PM2/25/15
Perhaps Delphi XE8 compiler can include a 48 bit integer and safe some

(No hardware support needed to implement this... at least memory-wise....
internally it could use 64 bit registers to do the computations... and still
load 48 bits of data... though I do see a bit of a problem there... the next
16 bits could be garbage... maybe zero them out... or add a special
instruction to read 48 bits from memory... or find another solution to only
read 48 bits of data into a 64 bit register).


Reply all
Reply to author
0 new messages