From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:36117) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UQJiX-00067d-A2 for qemu-devel@nongnu.org; Thu, 11 Apr 2013 11:47:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UQJiU-0003JN-II for qemu-devel@nongnu.org; Thu, 11 Apr 2013 11:47:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12330) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UQJiU-0003JI-Ak for qemu-devel@nongnu.org; Thu, 11 Apr 2013 11:47:14 -0400 Date: Thu, 11 Apr 2013 18:46:39 +0300 From: "Michael S. Tsirkin" Message-ID: <20130411154639.GC22779@redhat.com> References: <51658554.2000909@linux.vnet.ibm.com> <20130410174107.GB32247@redhat.com> <5165C60E.20006@linux.vnet.ibm.com> <20130411071927.GA17063@redhat.com> <5166B6B1.2030003@linux.vnet.ibm.com> <20130411134820.GA24942@redhat.com> <5166C19A.1040402@linux.vnet.ibm.com> <20130411143718.GC24942@redhat.com> <5166D460.2070106@linux.vnet.ibm.com> <5166D7D5.8080403@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5166D7D5.8080403@redhat.com> Subject: Re: [Qemu-devel] [RFC PATCH RDMA support v5: 03/12] comprehensive protocol documentation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, "Michael R. Hines" , owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com, gokul@us.ibm.com On Thu, Apr 11, 2013 at 05:33:41PM +0200, Paolo Bonzini wrote: > Il 11/04/2013 17:18, Michael R. Hines ha scritto: > > First of all, this whole argument should not even exist for the > > following reason: > > > > Page registrations are supposed to be *rare* - once a page is > > registered, it is registered for life. > > Uh-oh. That changes things a lot. We do not even need to benchmark the > various chunk sizes. > > > Third, this means that optimizing this protocol would not be helpful > > and that we should follow the "keep it simple" approach because > > during steady-state phase of the migration most of the pages should > > have already been registered. > > Ok, let's keep it simple. The only two things we need are: > > 1) remove the patch to disable is_dup_page > > 2) rename the transport to "x-rdma" (just in migration.c) > > Both things together let us keep it safe for a release or two. Let's > merge this thing. > > Paolo I would drop the chunk based thing too. Besides being slow, it turns out that it pins all memory anyway. So no memory overcommit. -- MST