From owner-freebsd-net Mon Oct 15 16: 0:23 2001 Delivered-To: freebsd-net@freebsd.org Received: from InterJet.dellroad.org (adsl-63-194-81-26.dsl.snfc21.pacbell.net [63.194.81.26]) by hub.freebsd.org (Postfix) with ESMTP id 0FD9537B405 for ; Mon, 15 Oct 2001 16:00:18 -0700 (PDT) Received: from arch20m.dellroad.org (arch20m.dellroad.org [10.1.1.20]) by InterJet.dellroad.org (8.9.1a/8.9.1) with ESMTP id PAA48049; Mon, 15 Oct 2001 15:49:19 -0700 (PDT) Received: (from archie@localhost) by arch20m.dellroad.org (8.11.3/8.11.3) id f9FMnJJ33076; Mon, 15 Oct 2001 15:49:19 -0700 (PDT) (envelope-from archie) From: Archie Cobbs Message-Id: <200110152249.f9FMnJJ33076@arch20m.dellroad.org> Subject: Re: strange results with increased net.inet.ip.intr_queue_maxlen In-Reply-To: <5.1.0.14.0.20011012121150.072325d0@marble.sentex.ca> "from Mike Tancsa at Oct 12, 2001 12:13:59 pm" To: Mike Tancsa Date: Mon, 15 Oct 2001 15:49:19 -0700 (PDT) Cc: freebsd-net@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL82 (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Mike Tancsa writes: > >If the forwarding path is maxed out, then it is the application layer's > >responsibility to back off (think TCP). > > Is it better for the networking layer to deal with this (potentially > introducing some latency) as opposed to letting the application ? Oops, can substitute "transport" for "application".. But no, the network should just do "best effort".. that is, unless you are a telco type in which case, go back to your X.25 :-) This is a religious issue to some degree, but in practice the war is over and the Internet won (vs. the telco way of doing things). There is probably a good paper somewhere outlining the "best effort" philosophy but I don't know what it is. Another way to look at it is intelligence in the leaf nodes rather than in the network. This is one of the central idea of the Internet dating back to a long time ago. I guess the other big idea is packets instead of dedicated circuits (which hog resources). > >Pinging is an excellent way to determine latency. > > I guess then its only at the "worst case" where I would see the added > latency as I dont see any difference by adjusting the queue size. Yes, you wouldn't notice a difference except when the queue is full all the time (the "worst case"). -Archie __________________________________________________________________________ Archie Cobbs * Packet Design * http://www.packetdesign.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message