From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH 0/5] not making corruption worse Date: Tue, 17 Mar 2015 15:54:02 -0700 Message-ID: References: <20150317072750.GA22155@peff.net> <20150317073730.GA25267@peff.net> Mime-Version: 1.0 Content-Type: text/plain Cc: git@vger.kernel.org, Michael Haggerty To: Jeff King X-From: git-owner@vger.kernel.org Tue Mar 17 23:54:12 2015 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1YY0NH-0001jS-GY for gcvg-git-2@plane.gmane.org; Tue, 17 Mar 2015 23:54:11 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932538AbbCQWyG (ORCPT ); Tue, 17 Mar 2015 18:54:06 -0400 Received: from pb-smtp1.int.icgroup.com ([208.72.237.35]:63806 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750958AbbCQWyF (ORCPT ); Tue, 17 Mar 2015 18:54:05 -0400 Received: from sasl.smtp.pobox.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id BB8213F571; Tue, 17 Mar 2015 18:54:04 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=fR3AVYtdm3MYZiUDegvotAcqpXI=; b=mmALl9 SibLLUwc1CKUDIQeXF3tCKg5ME2RUIPOiJf0df5xy3oEJ6ySLZ8JtEr+0GD/2LNE iCuQTXHot2JpEREaDSJdVOSfz6O2yriMGXS+PTil0DqTaS6tshBXBwcqThfJ+f0b rIgbEm6PMLjz/0WrtaG0eVdfLqXZsmjSGo9+c= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; q=dns; s=sasl; b=uuzGB+VI6LzriGcusmm6TINi9vQD1fOE 0fqub7igZ2O2nvN1ujZxgg64QnBsvsYStStKIRIBrNU6DvIOxJwFctzvaowCm7tr NFEcxGFPy4UXy1UXjm3035dsBAzIm6V2ubk9t6ZhYTpR30Acm1RxrMBuwqLvVIMD zhgrJ4HpeLs= Received: from pb-smtp1.int.icgroup.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id B3CCE3F570; Tue, 17 Mar 2015 18:54:04 -0400 (EDT) Received: from pobox.com (unknown [72.14.226.9]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by pb-smtp1.pobox.com (Postfix) with ESMTPSA id 31D963F56F; Tue, 17 Mar 2015 18:54:04 -0400 (EDT) In-Reply-To: <20150317073730.GA25267@peff.net> (Jeff King's message of "Tue, 17 Mar 2015 03:37:31 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-Pobox-Relay-ID: 828CB0A8-CCF8-11E4-896C-A2259F42C9D4-77302942!pb-smtp1.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jeff King writes: > But it strikes me as weird that we consider the _tips_ of history to be > special for ignoring breakage. If the tip of "bar" is broken, we omit > it. But if the tip is fine, and there's breakage three commits down in > the history, then doing a clone is going to fail horribly, as > pack-objects realizes it can't generate the pack. So in practice, I'm > not sure how much you're buying with the "don't mention broken refs" > code. I think this is a trade-off between strictness and convenience. Is it preferrable that every time you try to clone a repository you get reminded that one of its refs point at a bogus object and you instead have to do "git fetch $there" with a refspec that excludes the broken one, or is it OK to allow clones and fetches silently succeed as if nothing is broken? If the breakage in the reachability chain is somewhere that affects a branch that is actively in use by the project, with or without hiding a broken tip, you will be hit by object transfer failure and you need to really go in there and fix things anyway. If it is just a no-longer-used experimental branch that lost necessary objects, it may be more convenient if the system automatically ignored it. In some parts of the system there is a movement to make this trade off tweakable (hint: what happened to the knobs to fsck that allow certain kinds of broken objects in the object store? did the topic go anywhere?). This one so far lacked such a knob to tweak, and I view your paranoia bit as such a knob.