From owner-freebsd-current Wed Feb 27 10: 4:55 2002 Delivered-To: freebsd-current@freebsd.org Received: from avocet.prod.itd.earthlink.net (avocet.mail.pas.earthlink.net [207.217.120.50]) by hub.freebsd.org (Postfix) with ESMTP id 1E7A637B405; Wed, 27 Feb 2002 10:04:47 -0800 (PST) Received: from pool0329.cvx22-bradley.dialup.earthlink.net ([209.179.199.74] helo=mindspring.com) by avocet.prod.itd.earthlink.net with esmtp (Exim 3.33 #1) id 16g8RZ-0006Cm-00; Wed, 27 Feb 2002 10:04:46 -0800 Message-ID: <3C7D1F96.DC3969B7@mindspring.com> Date: Wed, 27 Feb 2002 10:04:06 -0800 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Matthew Dillon Cc: peter@FreeBSD.ORG, current@FreeBSD.ORG Subject: Re: you broke current in some weird way... etc References: <95075.1014756753@critter.freebsd.dk> <200202271733.g1RHXmh27846@apollo.backplane.com> <3C7D1A14.C3390B6C@mindspring.com> <200202271747.g1RHlOD27988@apollo.backplane.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Matthew Dillon wrote: > :> I'm just going to use this opportunity to plug the concept of temporary > :> sysctl-instrumentation for a commit like this. > : > :Overall, this is a good idea. However, it can't apply to > :any code that runs before init_main.c runs the SI_SUB_TUNABLES. > > Sure it does, because it means you can simply commit a change to the > default assignment for that sysctl rather then backing the whole thing > out to unbreak the general developer community. That saves a lot of > time and removes the 'oh hell, I have to track this down quickly!' > pressure. > > Sometimes features in early boot can be adjusted by breaking into DDB > and w/l changing the sysctl variable, but perhaps not in this case. Definitely not in this case. Similarly, there are a number of early allocations that occur by declaration, rather than by process, where the page mappings are then established post-facto, where it won't work. I really need to publish my "early life of FreeBSD" article. 8-(. I have all my extensive notes together, but I think it's at least a three-parter, and I need to expand the examples. I'll get around to it eventually, I promise. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message