From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36079) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eLz1m-0006rj-6i for qemu-devel@nongnu.org; Mon, 04 Dec 2017 17:15:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eLz1l-0008Ek-7C for qemu-devel@nongnu.org; Mon, 04 Dec 2017 17:15:54 -0500 References: <20171109141631.25688-1-vsementsov@virtuozzo.com> <8ade3dfe-ec27-a096-5d09-9e694f03935a@redhat.com> From: John Snow Message-ID: Date: Mon, 4 Dec 2017 17:15:45 -0500 MIME-Version: 1.0 In-Reply-To: <8ade3dfe-ec27-a096-5d09-9e694f03935a@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Qemu-block] [PATCH] blockdev-backup: enable non-root nodes for backup List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, qemu-block@nongnu.org Cc: kwolf@redhat.com, den@openvz.org, armbru@redhat.com On 12/01/2017 02:41 PM, Max Reitz wrote: > ((By the way, I don't suppose that's how it should work... But I don't > suppose that we want propagation of dirtying towards the BDS roots, do > we? :-/)) I have never really satisfactorily explained to myself what bitmaps on intermediate notes truly represent or mean. The simple case is "This layer itself serviced a write request." If that information is not necessarily meaningful, I'm not sure that's a problem except in configuration. ...Now, if you wanted to talk about bitmaps that associate with a Backend instead of a Node...