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Date: Wed, 19 Sep 2007 18:45:27 +1000
From: Peter Jeremy <peterjeremy@optushome.com.au>
To: Bruce Evans <brde@optusnet.com.au>
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Cc: arch@freebsd.org
Subject: Re: 64bit ticks, was Re: Changing p_swtime and td_slptime to ticks
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On 2007-Sep-19 14:55:35 +1000, Bruce Evans <brde@optusnet.com.au> wrote:
>I agree.  However, one variable isn't going to make much difference.  fs
>code is full of unecessary 64-bit calculations but no one notices the
>real-time pessimization from this, at least on non-low-end platforms (I
>only notice the code bloat).

I suspect the pessimization from the 64-bit arithmetic is masked by the
requirement that the FS code talk to (mostly rotating) media.  The cost
of an extra couple of instructions gets lost in the noise as soon as
you look at disk latencies.

--=20
Peter Jeremy

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