From owner-freebsd-current Mon Dec 14 15:30:21 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA29884 for freebsd-current-outgoing; Mon, 14 Dec 1998 15:30:21 -0800 (PST) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.40.131]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA29860; Mon, 14 Dec 1998 15:30:15 -0800 (PST) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.9.1/8.8.5) with ESMTP id AAA06843; Tue, 15 Dec 1998 00:23:01 +0100 (CET) To: "Jonathan M. Bresler" cc: johan@granlund.nu, julian@whistle.com, lars@akerlings.t.se, current@FreeBSD.ORG, isdn@FreeBSD.ORG Subject: Re: if_sppp is BROKEN!!! In-reply-to: Your message of "Mon, 14 Dec 1998 15:07:41 PST." <199812142307.PAA27390@hub.freebsd.org> Date: Tue, 15 Dec 1998 00:23:00 +0100 Message-ID: <6841.913677780@critter.freebsd.dk> From: Poul-Henning Kamp Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <199812142307.PAA27390@hub.freebsd.org>, "Jonathan M. Bresler" write s: >> Date: Mon, 14 Dec 1998 22:12:29 +0100 (CET) >> From: Johan Granlund >> >> This is really interesting! >> One of the concepts i liked in SYSV (ducking for cover) was streams and >> its ability to chain together modules to process a datastream. >> If it's coupled with kld to dynamically load/unload modules i think >> you have something _very_ good. >> >> That network thing. Can a module route a package thru different modules >> based on contents and state? > > the idea of streams is wonderful, the realization is costly. each > layer added (or module pushed) slows down processing and hurts > throughput. ritchie developed streams for serial, if i remember > correctly. streams was then applied to networks. there is an RFC > about layering being bad for networking and the relative performance > of NIT vs BPF prove the case. But with that said, there is still something to be said for modular and well defined interfaces. But streams ? No. They were great for async protocols, but they fail badly for packet stuff. -- Poul-Henning Kamp FreeBSD coreteam member phk@FreeBSD.ORG "Real hackers run -current on their laptop." "ttyv0" -- What UNIX calls a $20K state-of-the-art, 3D, hi-res color terminal To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message