From owner-freebsd-hackers@FreeBSD.ORG Tue May 17 09:29:46 2011 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 12156106566B for ; Tue, 17 May 2011 09:29:46 +0000 (UTC) (envelope-from rank1seeker@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 926808FC0A for ; Tue, 17 May 2011 09:29:45 +0000 (UTC) Received: by fxm11 with SMTP id 11so342133fxm.13 for ; Tue, 17 May 2011 02:29:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:message-id:from:to:subject:date:content-type :content-transfer-encoding:in-reply-to:references:x-mailer; bh=PiIrFOlwZLH7mcd+7Nv277tdRoNCwqdjNfFlcF80sOw=; b=pNpLwDioy9JbGqfrNzH0sCblXooIGQCDZMaW8Gn849+AHVUuUtpJEqSvhbG3rAIkf0 jzbj4cIj4KjFL9wbcQ7D238FB0bkrznGaWplNHSEFYwljvsbakQZ9cFL71UwzNQ9s5XE 6nZnqnpuvIvGdJPe+KTmSTWEbHkf4iEvzuqj4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:subject:date:content-type :content-transfer-encoding:in-reply-to:references:x-mailer; b=I5lqBkH2j9dp8eTE6VXrGuDEtVtaBWKb6fu+xDj+nmBmRjURSqq9xjKVfgjsjl9d/+ 0B8uwe8nvvWVrRbPwZo8MHvYBWEetQCFB4wBqiJTO0UwqQ0hLuHQZlzmA1Pw0lTrijaW ChSgeIy0pIXy60VTWxCd42dgp99tDF2Z9OUCg= Received: by 10.223.77.4 with SMTP id e4mr532317fak.51.1305624584442; Tue, 17 May 2011 02:29:44 -0700 (PDT) Received: from DEV ([82.193.208.173]) by mx.google.com with ESMTPS id d16sm129529faa.12.2011.05.17.02.29.28 (version=SSLv3 cipher=OTHER); Tue, 17 May 2011 02:29:43 -0700 (PDT) Message-ID: <20110517.092939.312.1@DEV> From: rank1seeker@gmail.com To: freebsd-hackers@freebsd.org Date: Tue, 17 May 2011 11:29:39 +0200 Content-Type: text/plain; charset="Windows-1250" Content-Transfer-Encoding: quoted-printable In-Reply-To: References: <20110516.183617.687.1@DEV> X-Mailer: POP Peeper (3.7.0.0) Subject: Re: MD ROOT and image size limitation (makes kernel panic) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 May 2011 09:29:46 -0000 > Hi,=0D=0A> =0D=0A> On Mon, May 16, 2011 at 11:36 AM, = wrote:=0D=0A> > I have a 4 GB or ram, so why = kernel panic with my MD ROOT, if larger then=0D=0A> > ~40 MB?=0D=0A> > = I've tried to split up root in 20MB image and usr in 160 MB=0D=0A> > Via = loader.conf root becomes md0 and usr md1 and panic occurs even = when=0D=0A> > they are split=0D=0A> >=0D=0A> > I had to get rid of md1, = to be able to boot with md0 as a root.=0D=0A> >=0D=0A> > What exactly = imposes limitation, inside kernel's code to SIZE of an image?=0D=0A> > My = hardware definatelly isn't ...=0D=0A> >=0D=0A> > Is this different on = amd64?=0D=0A> > I've tested this, only with i386.=0D=0A> >=0D=0A> =0D=0A> = We hit this problem at work and the solution was to increase NKPT.=0D=0A> = =0D=0A> If you are using -current then NKPT is already a kernel config = option.=0D=0A> With 8.x you will need to modify = .=0D=0A=0D=0A=0D=0AWell ..., it looks like my 8.2 RELEASE = src, has it, but ONLY for i386=0D=0A=0D=0A=0D=0A# less = /usr/src/sys/i386/conf/NOTES=0D=0A=0D=0A--=0D=0A#=0D=0A# Number of = initial kernel page table pages used for early bootstrap.=0D=0A# This = number should include enough pages to map the kernel, any=0D=0A# modules = or other data loaded with the kernel by the loader, and data=0D=0A# = structures allocated before the VM system is initialized such as = the=0D=0A# vm_page_t array. Each page table page maps 4MB (2MB with = PAE).=0D=0A#=0D=0Aoptions NKPT=3D31=0D=0A--=0D=0A=0D=0ASo, that = would be 124 MB for kernel and it's modules or other data loaded with the = kernel by the loader (i.e; md image)=0D=0AIn those nums, md image has = only about ~45 MB for itself.=0D=0A=0D=0AKernel itself and it's ..., = needs ~80 MB=0D=0A=0D=0A=0D=0AI'll build a custom kernel, for "lifting" = md image ...=0D=0A=0D=0A=0D=0A=0D=0ADomagoj Smol=E8i=E6=0D=0A=0D=0A