From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f198.google.com (mail-qk0-f198.google.com [209.85.220.198]) by kanga.kvack.org (Postfix) with ESMTP id E068C6B0270 for ; Fri, 29 Jun 2018 12:03:14 -0400 (EDT) Received: by mail-qk0-f198.google.com with SMTP id d64-v6so9674230qkb.23 for ; Fri, 29 Jun 2018 09:03:14 -0700 (PDT) Received: from mx1.redhat.com (mx3-rdu2.redhat.com. [66.187.233.73]) by mx.google.com with ESMTPS id t15-v6si9774268qta.327.2018.06.29.09.03.13 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 29 Jun 2018 09:03:13 -0700 (PDT) Subject: Re: [PATCH v34 0/4] Virtio-balloon: support free page reporting References: <1529928312-30500-1-git-send-email-wei.w.wang@intel.com> <5B35ACD5.4090800@intel.com> <4840cbb7-dd3f-7540-6a7c-13427de2f0d1@redhat.com> <5B36189E.5050204@intel.com> <34bb25eb-97f3-8a9f-8a13-401dfcf39a2c@redhat.com> <286AC319A985734F985F78AFA26841F7396C254C@shsmsx102.ccr.corp.intel.com> From: David Hildenbrand Message-ID: <745eb950-eb52-e32a-b006-5612a026c2dc@redhat.com> Date: Fri, 29 Jun 2018 18:03:09 +0200 MIME-Version: 1.0 In-Reply-To: <286AC319A985734F985F78AFA26841F7396C254C@shsmsx102.ccr.corp.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "Wang, Wei W" , "virtio-dev@lists.oasis-open.org" , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "kvm@vger.kernel.org" , "linux-mm@kvack.org" , "mst@redhat.com" , "mhocko@kernel.org" , "akpm@linux-foundation.org" Cc: "torvalds@linux-foundation.org" , "pbonzini@redhat.com" , "liliang.opensource@gmail.com" , "yang.zhang.wz@gmail.com" , "quan.xu0@gmail.com" , "nilal@redhat.com" , "riel@redhat.com" , "peterx@redhat.com" , Andrea Arcangeli , Luiz Capitulino >> Why would your suggestion still be applicable? >> >> Your point for now is "I might not want to have page hinting enabled due to >> the overhead, but still a live migration speedup". If that overhead actually >> exists (we'll have to see) or there might be another reason to disable page >> hinting, then we have to decide if that specific setup is worth it merging your >> changes. > > All the above "if we have", "assume we have" don't sound like a valid argument to me. Argument? *confused* And that hinders you from answering the question "Why would your suggestion still be applicable?" ? Well, okay. So I will answer it by myself: Because somebody would want to disable page hinting. Maybe there are some people out there. > >> I am not (and don't want to be) in the position to make any decisions here :) I >> just want to understand if two interfaces for free pages actually make sense. > > I responded to Nitesh about the differences, you may want to check with him about this. > I would suggest you to send out your patches to LKML to get a discussion with the mm folks. Indeed, Nitesh is trying to solve the problems we found in the RFC, so this can take some time. > > Best, > Wei > -- Thanks, David / dhildenb