From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:52344) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UIKot-000582-HG for qemu-devel@nongnu.org; Wed, 20 Mar 2013 11:20:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UIKoe-000269-K8 for qemu-devel@nongnu.org; Wed, 20 Mar 2013 11:20:51 -0400 Received: from mail-wi0-x22f.google.com ([2a00:1450:400c:c05::22f]:55031) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UIKoe-00025w-CG for qemu-devel@nongnu.org; Wed, 20 Mar 2013 11:20:36 -0400 Received: by mail-wi0-f175.google.com with SMTP id c10so82260wiw.8 for ; Wed, 20 Mar 2013 08:20:33 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <5149D3B0.2070500@redhat.com> Date: Wed, 20 Mar 2013 16:20:16 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1363576743-6146-1-git-send-email-mrhines@linux.vnet.ibm.com> <1363576743-6146-9-git-send-email-mrhines@linux.vnet.ibm.com> <5146D9BF.3030407@redhat.com> <51477A26.8090600@linux.vnet.ibm.com> <51482D78.3010301@redhat.com> <5148643F.2070401@linux.vnet.ibm.com> <51486733.7060207@redhat.com> <51486AD0.80309@linux.vnet.ibm.com> <51486C0D.2040609@redhat.com> <514871C2.5020108@linux.vnet.ibm.com> <5148748C.5050509@redhat.com> <5148AE2F.2030206@linux.vnet.ibm.com> <5148B137.4070300@redhat.com> In-Reply-To: <5148B137.4070300@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH RDMA support v4: 08/10] introduce QEMUFileRDMA List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: aliguori@us.ibm.com, mst@redhat.com, qemu-devel@nongnu.org, "Michael R. Hines" , owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com, gokul@us.ibm.com Il 19/03/2013 19:40, Paolo Bonzini ha scritto: >>> >> That however gives me an idea... Instead of the full drain at the end >>> >> of an iteration, does it make sense to do a "partial" drain at every >>> >> chunk full, so that you don't have > N bytes pending and the downtime is >>> >> correspondingly limited? >> > >> > >> > Sure, you could do that, but it seems overly complex just to avoid >> > a single flush() call at the end of each iteration, right? > Would it really be that complex? Not having an extra QEMUFile op > perhaps balances that complexity (and the complexity remains hidden in > rdma.c, which is an advantage). > > You could alternatively drain every N megabytes sent, or something like > that. But a partial drain would help obeying the maximum downtime > limitations. On second thought: just keep the drain operation, but make it clear that it is related to the new save_ram_page QEMUFileOps field. You could call it flush_ram_pages or something like that. Paolo