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Date: Sat, 29 Jul 2006 22:15:31 +0100
From: Brian Candler <B.Candler@pobox.com>
To: Peter Jeremy <peterjeremy@optushome.com.au>
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Cc: Michal Mertl <mime@traveller.cz>, freebsd-current@freebsd.org
Subject: Re: vmstat's entries type
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On Sun, Jul 30, 2006 at 06:56:55AM +1000, Peter Jeremy wrote:
> On Sat, 2006-Jul-29 18:13:32 +0200, Michal Mertl wrote:
> >#define PCPU_LAZY_INC(var)      (++*PCPU_PTR(var))
> 
> I missed that.
> 
> >and function vcnt from sys/vm/vm_meter.c
> 
> vcnt() accumulates multiple 32-bit counters into a 32-bit result.  Getting
> a 64-bit result means additionally tracking overflows in each counter.

But if you have per-CPU counters, there's no problem with accumulating
64-bit values in the first place.

So in the above macro I don't see why 'var' can't be a pointer to a
uint64_t, with relevant minor changes to vcnt() of course.

Regards,

Brian.