From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:42378) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UWsBW-0004XA-6W for qemu-devel@nongnu.org; Mon, 29 Apr 2013 13:48:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UWsBU-0003FK-IK for qemu-devel@nongnu.org; Mon, 29 Apr 2013 13:48:18 -0400 Received: from g4t0014.houston.hp.com ([15.201.24.17]:29705) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UWsBU-0003CT-Aa for qemu-devel@nongnu.org; Mon, 29 Apr 2013 13:48:16 -0400 Message-ID: <517EB258.20808@hp.com> Date: Mon, 29 Apr 2013 10:48:08 -0700 From: Chegu Vinod MIME-Version: 1.0 References: <1367095836-19318-1-git-send-email-chegu_vinod@hp.com> <517E8979.6090103@redhat.com> In-Reply-To: <517E8979.6090103@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH v2] Throttle-down guest when live migration does not converge. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: pbonzini@redhat.com, owasserm@redhat.com, qemu-devel@nongnu.org, anthony@codemonkey.ws, quintela@redhat.com On 4/29/2013 7:53 AM, Eric Blake wrote: > On 04/27/2013 02:50 PM, Chegu Vinod wrote: >> Busy enterprise workloads hosted on large sized VM's tend to dirty >> memory faster than the transfer rate achieved via live guest migration. >> Despite some good recent improvements (& using dedicated 10Gig NICs >> between hosts) the live migration does NOT converge. >> >> No exernal trigger is required (unlike option 1) and it can co-exist > s/exernal/external/ > >> with enhancements being pursued as part of Option 2 (e.g. RDMA). >> >> Thanks to Juan and Paolo for their useful suggestions. >> >> --- >> >> (qemu) info migrate >> capabilities: xbzrle: off auto-converge: on <---- > This part looks nice. > > I'm not reviewing the entire patch (I'm not an expert on the internals > of migration), but just the interface: Thanks for taking a look at this. I shall incorporate your suggested changes in the next version. Hoping to hear from Juan/Orit and others on the live migration part. Thanks, Vinod >> +++ b/qapi-schema.json >> @@ -599,10 +599,14 @@ >> # This feature allows us to minimize migration traffic for certain work >> # loads, by sending compressed difference of the pages >> # >> +# @auto-converge: Controls whether or not the we want the migration to >> +# automaticially detect and force convergence by slowing > s/automaticially/automatically/ > >> +# down the guest. Disabled by default. > Missing a (since 1.6) designation. > > Also, use of first-person (us, we) in docs seems a bit unprofessional, > although you were copying pre-existing usage. How about: > > @xbzrle: Migration supports xbzrle (Xor Based Zero Run Length Encoding), > which minimizes migration traffic for certain workloads by > sending compressed differences of active pages > > @auto-converge: Migration supports automatic throttling of guest > activity to force convergence (since 1.6) >