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Date: Tue, 3 Apr 2001 21:06:35 -0400 (EDT)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
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To: Alfred Perlstein <alfred@FreeBSD.org>
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Subject: Re: cvs commit: src/sys/sys mbuf.h src/sys/kern uipc_mbuf.c
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<<On Tue, 3 Apr 2001 17:35:29 -0700, Alfred Perlstein <alfred@FreeBSD.org> said:

> While this is a good idea, it doesn't give us a consistant view of
> the stats without additional atomic ops or critical regions.

Atomic operations are likely to be cheaper on modern platforms than
locking.  In any case, you can simply keep per-CPU stats and then
summarize when they are requested, which is even cheaper, since the
stats are updated FAR more frequently than they are inspected.

-GAWollman


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