From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:42612) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QIL01-000637-Ue for qemu-devel@nongnu.org; Fri, 06 May 2011 09:23:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QIL01-0008W0-0G for qemu-devel@nongnu.org; Fri, 06 May 2011 09:23:17 -0400 Received: from mail-gx0-f173.google.com ([209.85.161.173]:51646) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QIL00-0008Vw-Si for qemu-devel@nongnu.org; Fri, 06 May 2011 09:23:16 -0400 Received: by gxk26 with SMTP id 26so1371500gxk.4 for ; Fri, 06 May 2011 06:23:16 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4DBAAA90.6010007@redhat.com> References: <1303910855-28999-1-git-send-email-stefanha@linux.vnet.ibm.com> <1303910855-28999-3-git-send-email-stefanha@linux.vnet.ibm.com> <4DBAAA90.6010007@redhat.com> Date: Fri, 6 May 2011 14:23:16 +0100 Message-ID: From: Stefan Hajnoczi Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 2/8] qmp: Add QMP support for stream commands List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Anthony Liguori , Adam Litke , Stefan Hajnoczi , qemu-devel@nongnu.org On Fri, Apr 29, 2011 at 1:09 PM, Kevin Wolf wrote: > Am 27.04.2011 15:27, schrieb Stefan Hajnoczi: >> From: Anthony Liguori >> >> For leaf images with copy on read semantics, the stream commands allow t= he user >> to populate local blocks by manually streaming them from the backing ima= ge. >> Once all blocks have been streamed, the dependency on the original backi= ng >> image can be removed. =A0Therefore, stream commands can be used to imple= ment >> post-copy live block migration and rapid deployment. >> >> The stream command can be used to stream a single sector, to start strea= ming >> the entire device, and to cancel an active stream. =A0It is easiest to a= llow the >> stream command to manage streaming for the entire device but a managent = tool >> could use single sector mode to throttle the I/O rate. =A0When a single = sector is >> streamed, the command returns an offset that can be used for a subsequen= t call. > > You mean literally single sectors? You're not interested in completing > the job in finite time, are you? ;-) > > I would suggest adding a length argument for the all=3Dfalse case, so tha= t > management tools can choose more reasonable sizes. Discussion on libvir-list suggests the same thing. Let's take a nb_sectors where 0=3Dall. Stefan