[POLLING] strange interrupt/system load

[Barney Cordoba]

--- On Sun, 9/13/09, rihad <rihad at mail.ru> wrote:

> From: rihad <rihad at mail.ru>
> Subject: Re: [POLLING] strange interrupt/system load
> To: "Barney Cordoba" <barney_cordoba at yahoo.com>
> Cc: freebsd-net at freebsd.org
> Date: Sunday, September 13, 2009, 10:33 AM
> Barney Cordoba wrote:
> > 
> > --- On Sun, 9/13/09, rihad <rihad at mail.ru>
> wrote:
> >> What's wrong with 64 bits?
> > 
> > I haven't spent a large portion of my life trying to
> figure
> > it out exactly, but I'd guess that the larger size of
> the structures and code results in fewer cache hits.
> 
> Then what's wrong with also doubling cache sizes?

Your logic is faulty here. Doubling the cache size also would 
increase the performance of the 32 bit version. In fact you'd 
probably increase the advantage of running in 32 bit mode.

> Besides, apart from other benefits, 64-bit makes every-day
> big number arithmetic a single CPU instruction as opposed to
> several instructions required on 32-bit CPUs through bignum
> emulation.


You move a lot more memory than you do math in an OS. Perhaps
a benchmark to calculate the US national debt would benefit, but
its not going to do much for the FreeBSD network stack.

Barney