From owner-freebsd-hackers Wed Jan 10 19:25:11 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id TAA25146 for hackers-outgoing; Wed, 10 Jan 1996 19:25:11 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id TAA25141 for ; Wed, 10 Jan 1996 19:25:06 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id UAA16434; Wed, 10 Jan 1996 20:21:02 -0700 From: Terry Lambert Message-Id: <199601110321.UAA16434@phaeton.artisoft.com> Subject: Re: pppd vs ijppp To: dennis@etinc.com (dennis) Date: Wed, 10 Jan 1996 20:21:02 -0700 (MST) Cc: nate@rocky.sri.MT.net, hackers@FreeBSD.org In-Reply-To: <199601102345.SAA00248@etinc.com> from "dennis" at Jan 10, 96 06:45:24 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@FreeBSD.org Precedence: bulk > Yes...actually i have a pretty good idea what im talking about. > There are things that belong in the kernel and things that dont. > Thinks that interarct with > USERS > clearly belong in user space, because you can't save a process > switch anyway and users are clearly an incremental variable. ppp, > on the otherhand, is a network interface, whose traffic is most > usually routed to another network interface. Since > everything > else is in the kernel, its nonsensical to pull data out just to > do a tiny bit of processing (probably none actually) just to push > it back in. Your beating up your system for no reason, and if > you're charging customers then your cheating them as well. Er. I think you are confusing implementation details with implementability. Typically I mmap the buffer area in my applications, which saves me the copy because the mapping is the same in both spaces after I ioctl the buffer address to a driver to lock the pages down and get their absolute address for later use by the kernel. Context switch overhead for a given MTU of serial data before a packet end is *nothing* if implemented as a line discipline. Is this a case of missing the forest for the trees? Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.