Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936197Ab3DIURq (ORCPT ); Tue, 9 Apr 2013 16:17:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9155 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936020Ab3DIURo (ORCPT ); Tue, 9 Apr 2013 16:17:44 -0400 Date: Tue, 9 Apr 2013 22:12:18 +0300 From: "Michael S. Tsirkin" To: Roland Dreier Cc: "Michael R. Hines" , Jason Gunthorpe , Sean Hefty , Hal Rosenstock , Yishai Hadas , Christoph Lameter , "linux-rdma@vger.kernel.org" , LKML , qemu-devel@nongnu.org Subject: Re: [PATCHv2] rdma: add a new IB_ACCESS_GIFT flag Message-ID: <20130409191218.GD8212@redhat.com> References: <20130324155153.GA8597@redhat.com> <515F3160.4020007@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1067 Lines: 26 On Fri, Apr 05, 2013 at 01:43:49PM -0700, Roland Dreier wrote: > On Fri, Apr 5, 2013 at 1:17 PM, Michael R. Hines > wrote: > > I also removed the IBV_*_WRITE flags on the sender-side and activated > > cgroups with the "memory.memsw.limit_in_bytes" activated and the migration > > with RDMA also succeeded without any problems (both with *and* without GIFT > > also worked). > > Not sure I'm interpreting this correctly. Are you saying that things > worked without actually setting the GIFT flag? In which case why are > we adding this flag? > > - R. We are adding the flag to reduce memory when there's lots of COW pages. There's no guarantee there will be COW pages so I expect things to work both with and without breaking COW, just using much more memory when we break COW. -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/