From owner-freebsd-hackers@FreeBSD.ORG  Wed Jun  2 15:29:47 2004
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Date: Wed, 2 Jun 2004 15:29:47 -0700
From: Luigi Rizzo <rizzo@icir.org>
To: "Christian S.J. Peron" <csjp@freebsd.org>
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In-Reply-To: <20040602221443.GA92431@freefall.freebsd.org>;
	from csjp@freebsd.org on Wed, Jun 02, 2004 at 03:14:43PM -0700
cc: hackers@freebsd.org
cc: Andre Oppermann <andre@freebsd.org>
cc: ipfw@freebsd.org
Subject: Re: ipfw cached ucred patch
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On Wed, Jun 02, 2004 at 03:14:43PM -0700, Christian S.J. Peron wrote:
> 
> I understand what you are saying. The only real other choice 
> would be to copy out the entire cr_groups array. Do you know
> if this copy would be more expensive then the mutex lock/unlock
> associated with grabbing a reference to the ucred?

i bet the copy it would be cheaper almost on any architecture -- it
is only 64 bytes anyways, with these sizes what kills you in memory
accesses is the latency, not the throughput.

cheers
luigi