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Date:      Sun, 13 Sep 2009 17:26:18 +0200
From:      Erik Trulsson <ertr1013@student.uu.se>
To:        rihad <rihad@mail.ru>
Cc:        Barney Cordoba <barney_cordoba@yahoo.com>, freebsd-net@freebsd.org
Subject:   Re: [POLLING] strange interrupt/system load
Message-ID:  <20090913152618.GA1618@owl.midgard.homeip.net>
In-Reply-To: <4AAD02A2.5060207@mail.ru>
References:  <94372.57247.qm@web63906.mail.re1.yahoo.com> <4AAD02A2.5060207@mail.ru>

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On Sun, Sep 13, 2009 at 07:33:06PM +0500, rihad wrote:
> Barney Cordoba wrote:
> > 
> > --- On Sun, 9/13/09, rihad <rihad@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?

Increasing the size of the CPU cache not only makes it more expensive to
manufacture, but also makes it slightly slower to access.

> 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.

True, and if you need to perform a lot of 64-bit arithmetic then the extra
register width can indeed be a major win.
Most people, on most systems, have very limited need of 64-bit arithmetic.



-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013@student.uu.se



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