From owner-freebsd-current@FreeBSD.ORG  Tue May 25 06:12:23 2004
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7C29016A4CE
	for <freebsd-current@freebsd.org>;
	Tue, 25 May 2004 06:12:23 -0700 (PDT)
Received: from mail.sandvine.com (sandvine.com [199.243.201.138])
	by mx1.FreeBSD.org (Postfix) with ESMTP id E9ACA43D46
	for <freebsd-current@freebsd.org>;
	Tue, 25 May 2004 06:12:22 -0700 (PDT)
	(envelope-from don@sandvine.com)
Received: by mail.sandvine.com with Internet Mail Service (5.5.2657.72)
	id <KYKJY6QV>; Tue, 25 May 2004 09:12:05 -0400
Message-ID: <FE045D4D9F7AED4CBFF1B3B813C85337051D8D2A@mail.sandvine.com>
From: Don Bowman <don@sandvine.com>
To: 'Sergey Lyubka' <devnull@uptsoft.com>,
	freebsd-current@freebsd.org
Date: Tue, 25 May 2004 09:12:04 -0400
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2657.72)
Content-Type: text/plain;
	charset="iso-8859-1"
Subject: RE: 5.2.1 + snort, dropping packets
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 25 May 2004 13:12:23 -0000

From: Sergey Lyubka [mailto:devnull@uptsoft.com]
> hackers,
> I am running snort on 5.2.1-RELEASE, and I am getting high
> dropped packets rate. traffic is quiet, about 1kpps, the box 
> runs on xeon
> processor, intel gigabit NICs (em driver), system load is low:
> 
> CPU states:  1.9% user,  5.1% nice,  1.6% system,  4.7% 
> interrupt, 86.8% idle
> Mem: 121M Active, 97M Inact, 75M Wired, 736K Cache, 60M Buf, 201M Free
> Swap: 512M Total, 512M Free
> 
> 
> I have tried:
> 	o both SMP and UP kernels
> 	o both SCHED_ULE and SCHED_4BSD options
> 	o libpcap libs versions 0.7 and 0.8.3
> 	o 5.2.1-RELEASE and -current kernels
> 	o DEVICE_POLLING option
> 	o sysctl debug.bpf_bufsize set to maximum of 524288
> 
> and still having dropped packets.
> I am having a much lower spec box, running obsd 3.2, same 
> snort configuration,
> capturing the same traffic. obsd shows constant 0 dropped packets.
> 
> How would I fix that problem?

This might be old information, but on stable branch, libpcap
overrode the 'debug.bpf_bufsize' and always made it 4K. I made
a local change and it fixed it for me. Not sure if that is
corrected on current.

On the system you indicate you should be able to get ~300Kpps
into user space via bpf, or at least, you can with stable.