From owner-freebsd-hackers Sat Feb 23 10:40:20 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from rwcrmhc53.attbi.com (rwcrmhc53.attbi.com [204.127.198.39]) by hub.freebsd.org (Postfix) with ESMTP id 0ADB237B42F; Sat, 23 Feb 2002 10:40:15 -0800 (PST) Received: from InterJet.elischer.org ([12.232.206.8]) by rwcrmhc53.attbi.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP id <20020223184014.USSB2951.rwcrmhc53.attbi.com@InterJet.elischer.org>; Sat, 23 Feb 2002 18:40:14 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id KAA79312; Sat, 23 Feb 2002 10:34:51 -0800 (PST) Date: Sat, 23 Feb 2002 10:34:49 -0800 (PST) From: Julian Elischer To: Bakul Shah Cc: Terry Lambert , Michael Smith , "George V. Neville-Neil" , freebsd-hackers@freebsd.org Subject: Re: Kernel Debugging over the Ethernet? In-Reply-To: <200202231726.MAA07523@marlborough.cnchost.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, 23 Feb 2002, Bakul Shah wrote: > > Without TCP, you have to implement your own version of > > retry and ack (equivalent to negotiating a window size > > of 1), and so you have to redo what's already there. > > Would be nice to have a reliable channel but in our > experience not having this was not a big deal. The gdb > serial protocol is fairly resilient. > > > The other issue with TCP is that you can set up specific > > flows in the company firewall, and also permit SSLeay > > based tunnel encapsulation from outside via an intermediate > > machine. This isn't really required for off-site debugging, > > but it gives another option. > > You are better off ssh-ing into a machine on the same net and > running gdb there. > > For me the biggest reason for not using any IP was to > minimize any perturbation due to the debugger. The fact that > we have to steal mbufs is bad enough. I agree, especially when we will have locking etc for the mbuf queues. It's a pitty we can't intercept the mbuf allocate routines.. then we could keep a couple for ourself :-) > > -- bakul > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message