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Date: Sun, 2 Jan 2005 10:31:28 -0500
From: Bill Moran <wmoran@potentialtech.com>
To: freebsd-questions@freebsd.org
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Subject: Re: TCPDUMP performance
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James Kilton <kilton9@yahoo.com> wrote:

> Hello,
> 
> We've installed some FreeBSD machines as Gigabit sniffers, and I'm
> wondering if there are any things I can tweak (e.g., buffer size) to help
> TCPDUMP capture better (we often see packets dropped by the kernel).
> 
> Any advice would be appreciated.

When using tethereal to do captures, I found that nicing the capture
process reduced the incidence of dropped packets to 0.

Not exactly the same circumstance, but I would guess that tcpdump would
respond simularly.

-- 
Bill Moran
Potential Technologies
http://www.potentialtech.com