Re: your mail

[Jun Sun <jsun@mvista.com>]

On Thu, Apr 17, 2003 at 10:53:57AM -0700, Dennis Castleman wrote:
> ALL
> 
> Anybody know the performance differences I can expect using a MIPS 5K core
> @250 Mhz in 64bit mode versus 32bit mode?
>

It really depends on the applications.  The biggest gain from 64bit,
other than the obviously bigger address space, is 64bit data
manipulation.  A single 64bit instruction (add/sub/...) is carried
out by several instructions in 32bit.

If your apps are heavy on 64bit operations, then you gain.
Otherwise I suspect no performance gain or even possibly a little 
worse performance due more stress on cache/memory subsystems.

I am sure others with more 64bit experience probably have more 
to say.  :)


Jun