From owner-freebsd-doc Mon Aug 26 2:45:31 2002 Delivered-To: freebsd-doc@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6649837B400 for ; Mon, 26 Aug 2002 02:45:28 -0700 (PDT) Received: from Kain.sumuk.de (Kain.sumuk.de [213.221.86.114]) by mx1.FreeBSD.org (Postfix) with ESMTP id 10B8A43E75 for ; Mon, 26 Aug 2002 02:45:27 -0700 (PDT) (envelope-from martin@sumuk.de) Received: from Moses.earth.sol (Moses.earth.sol [192.168.1.1]) by Kain.sumuk.de (8.12.5/8.12.5) with ESMTP id g7Q9j9bn072700; Mon, 26 Aug 2002 11:45:09 +0200 (CEST) (envelope-from martin@sumuk.de) Received: (from vincent@localhost) by Moses.earth.sol (8.11.6/8.11.6) id g7Q9j7p09543; Mon, 26 Aug 2002 11:45:07 +0200 (CEST) (envelope-from vincent) Date: Mon, 26 Aug 2002 11:45:06 +0200 From: Martin Heinen To: Giorgos Keramidas Cc: Martin Heinen , "Ritz, Bruno" , FreeBSD-doc@FreeBSD.ORG Subject: Re: possible millisecond - microsecond confusion Message-ID: <20020826114506.A8041@sumuk.de> References: <20020825125050.A6559@sumuk.de> <20020825140556.GF762@hades.hell.gr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20020825140556.GF762@hades.hell.gr>; from keramida@ceid.upatras.gr on Sun, Aug 25, 2002 at 05:05:57PM +0300 Sender: owner-freebsd-doc@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Sun, Aug 25, 2002 at 05:05:57PM +0300, Giorgos Keramidas wrote: > On 2002-08-25 12:50 +0000, Martin Heinen wrote: > > Indeed, it seems strange to use ms and microseconds in the same > > sentence. How about the attached patch, which changes microseconds > > to ?s? > > Actually, it's probably "milliseconds" you want to keep. Microseconds > seems like a very small amount of time for processing a packet. I > could be wrong, though. If you want to change it to microseconds, > you'd also have to update numbers like "370 packets per second". If we omit the time for processing the rules, the sentences will be less confusing. These numbers are not used in the following and a reader may easily calculate them if he really needs them. How does this one look? ***** Index: chapter.sgml =================================================================== RCS file: /u/cvs/doc/en_US.ISO8859-1/books/handbook/security/chapter.sgml,v retrieving revision 1.114 diff -u -r1.114 chapter.sgml --- chapter.sgml 18 Aug 2002 17:22:15 -0000 1.114 +++ chapter.sgml 26 Aug 2002 09:40:28 -0000 @@ -2682,14 +2682,14 @@ any. The per-packet processing overhead in the former case was - approximately 2.703ms/packet, or roughly 2.7 microseconds per - rule. Thus the theoretical packet processing limit with these + approximately 2.703ms/packet. + Thus the theoretical packet processing limit with these rules is around 370 packets per second. Assuming 10Mbps Ethernet and a ~1500 byte packet size, we would only be able to achieve a 55.5% bandwidth utilization. For the latter case each packet was processed in - approximately 1.172ms, or roughly 1.2 microseconds per rule. + approximately 1.172ms. The theoretical packet processing limit here would be about 853 packets per second, which could consume 10Mbps Ethernet bandwidth. ***** -- Marxpitn To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-doc" in the body of the message