From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756083Ab2ITQKE (ORCPT ); Thu, 20 Sep 2012 12:10:04 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:55905 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756006Ab2ITQKD convert rfc822-to-8bit (ORCPT ); Thu, 20 Sep 2012 12:10:03 -0400 Message-Id: <505B5C0C020000780009CC14@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.0 Date: Thu, 20 Sep 2012 17:10:20 +0100 From: "Jan Beulich" To: "Oliver Chick" Cc: "David Vrabel" , "xen-devel@lists.xen.org" , "Konrad Rzeszutek Wilk" , "linux-kernel@vger.kernel.org" Subject: Re: [Xen-devel] [PATCH] Persistent grant maps for xen blk drivers References: <1348051887-21885-1-git-send-email-oliver.chick@citrix.com> <505AF126.2050806@citrix.com> <1348140637.24539.32.camel@oliverchick-Precision-WorkStation-T3400> <505B1EB9020000780009CA6E@nat28.tlf.novell.com> <20120920134951.GC1998@localhost.localdomain> <1348150422.24539.58.camel@oliverchick-Precision-WorkStation-T3400> In-Reply-To: <1348150422.24539.58.camel@oliverchick-Precision-WorkStation-T3400> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> On 20.09.12 at 16:13, Oliver Chick wrote: > 3) Having blkback inform blkfront on startup as to how many grefs it is > willing to persistently-map. We then hit the same question again though: > what should be do if blkfront ignores this limit? Not really - if any information coming from the backend is being ignored by the frontend, then it certainly can't expect consistent performance. Jan