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Date: Sun, 23 Jul 2006 19:48:36 +0200
From: =?ISO-8859-1?Q?Sten_Daniel_S=F8rsdal?= <lists@wm-access.no>
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To: "M. Warner Losh" <imp@bsdimp.com>
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Cc: freebsd-current@freebsd.org
Subject: Re: vmstat's entries type
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M. Warner Losh wrote:
>
> One approach that we could use for 64-bit counters would be to just
> use 32-bits one, and poll them for overflow and bump an overflow
> count.  This assumes that the 32-bit counters overflow much less often
> than the polling interval, and easily triples the amount of storage
> for each of them...  It is ugly :-(
>=20

What's wrong with the add+adc (asm) approach found on any i386?
It would cost you just a few cpu cycles unless i'm mistaken.

--=20
Sten Daniel S=F8rsdal