From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38977) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anRGI-0002gN-J4 for qemu-devel@nongnu.org; Tue, 05 Apr 2016 09:43:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1anRGF-0004DS-E9 for qemu-devel@nongnu.org; Tue, 05 Apr 2016 09:43:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44673) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anRGF-0004DM-7d for qemu-devel@nongnu.org; Tue, 05 Apr 2016 09:43:15 -0400 References: <1459787950-15286-1-git-send-email-eblake@redhat.com> <20160405040527.GA4183@noname.redhat.com> From: Paolo Bonzini Message-ID: <5703C0EC.6080306@redhat.com> Date: Tue, 5 Apr 2016 15:43:08 +0200 MIME-Version: 1.0 In-Reply-To: <20160405040527.GA4183@noname.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] doc: Add NBD_CMD_BLOCK_STATUS extension List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf , Eric Blake Cc: nbd-general@lists.sourceforge.net, qemu-devel@nongnu.org, Pavel Borzenkov , Stefan Hajnoczi , Wouter Verhelst , "Denis V. Lunev" On 05/04/2016 06:05, Kevin Wolf wrote: > The options I can think of is adding a request field "max number of > descriptors" or a flag "only single descriptor" (with the assumption > that clients always want one or unlimited), but maybe you have a better > idea. I think a limit is better. Even if the client is ultimately going to process the whole file, it may take a very long time and space to retrieve all the descriptors in one go. Rather than query e.g. 16GB at a time, I think it's simpler to put a limit of 1024 descriptors or so. Paolo