From owner-freebsd-current@FreeBSD.ORG Mon Jan 30 16:59:10 2012 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 007541065675 for ; Mon, 30 Jan 2012 16:59:10 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 4E0348FC1C for ; Mon, 30 Jan 2012 16:59:08 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id SAA21035; Mon, 30 Jan 2012 18:59:06 +0200 (EET) (envelope-from avg@FreeBSD.org) Message-ID: <4F26CC5A.2070501@FreeBSD.org> Date: Mon, 30 Jan 2012 18:59:06 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:9.0) Gecko/20120111 Thunderbird/9.0 MIME-Version: 1.0 To: freebsd-current@FreeBSD.org X-Enigmail-Version: 1.3.5 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Subject: revisiting tunables under Safe Mode menu option X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 30 Jan 2012 16:59:10 -0000 First, I think that this proposal/discussion could have been more useful before the 9.0. Maybe the RE would be interested in adding another item to their pre-release checklist: ask developers about what could be dropped and what should be added to the Safe Mode settings in a new (.0) release. Probably the developers should keep the Safe Mode in mind too when adding new features or making other drastic changes, but the reminder should be welcome. What we have for Safe Mode now (from menu-commands.4th): > \ > \ Toggle ACPI elements if necessary > \ > acpipresent? if acpienabled? if > menuacpi @ dup 0<> if > toggle_menuitem ( N -- N ) > then > drop > acpi_disable > then then > > s" set hint.apic.0.disabled=1" evaluate > s" set hw.ata.ata_dma=0" evaluate > s" set hw.ata.atapi_dma=0" evaluate > s" set hw.ata.wc=0" evaluate > s" set hw.eisa_slots=0" evaluate > s" set hint.kbdmux.0.disabled=1" evaluate o Since we have a separate ACPI option and because ACPI now is almost a mandatory thing (and not a significant source of boot troubles), maybe we could remove the code that automatically disables ACPI in Safe Mode? o hint.apic.0.disabled - APIC code doesn't seem to be a significant source of boot troubles, like ACPI it has become almost a mandatory thing. So maybe we should remove this setting? o hw.ata.ata_dma, hw.ata.atapi_dma - I am not sure if there have been any significant problems with ATA DMA recently. Maybe these could be removed? o hw.ata.wc - I am not sure if this setting is relevant to the safe boot. Another candidate for removal? o hw.eisa_slot - Looks like something from ancient times. Probably just irrelevant for most systems. o hint.kbdmux.0.disabled - I do not recall any recent problems with kbdmux. In fact disabling it may produce a surprising behavior for a user if there are multiple keyboards actually attached. Just so that the Safe Mode doesn't turn into a NOP I propose to add the following tunables: o kern.eventtimer.periodic=1 - Use periodic timer to drive clocks just in case a system has any problems with the default mode. Example: PR 164457. o kern.geom.part.check_integrity=0 - Let GPART code be more permissive, could be useful during upgrades from earlier versions of FreeBSD or when multi-booting with other OSes. o More? -- Andriy Gapon