Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp74811imm; Tue, 17 Jul 2018 21:11:21 -0700 (PDT) X-Google-Smtp-Source: AAOMgpfQ4w8lmzCh68VdY/YsObwXLuAcaul8faHF/miHXi8CCA7HyTXk+xYwhcve0NtumcrutTLP X-Received: by 2002:a62:ee01:: with SMTP id e1-v6mr3501104pfi.2.1531887081131; Tue, 17 Jul 2018 21:11:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1531887081; cv=none; d=google.com; s=arc-20160816; b=Usr2xkYi2a9oRDpy2z9P5+IZyKzn4jVtqTlCkZR9vhtzCzPPQHt3Nt3Z6F4QbwA+8B /utTfuUpyNV4o3inn8Umy4o6W3yCvTuyVTPSWjuxE09WjGLWJFeXd8wWJT6Ax+cGibR/ eO/pFMHA26AjJL0FcM0E19c/aLX9Q/XNdweBQ8Q8F9XqMRJhIQ0aIxy/37lKA/UFTKw5 7coTqx9DrnI9+gMvty0Rb9uwfHCHzYiFOdU7fg2zUQR1HBBLikuRJPQ3BE8nEnUh60t9 sSm0nCb81Tlo3T6AKM8K8WAtJIG3xJBM+IPejQchO/AHJ7nWkRRmJY8AOO3DdOjc+vAQ DIhQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date :arc-authentication-results; bh=sVOl2tbPwpFpb3SoUkBAxn/688hfJ2Os94nm+j7SgIY=; b=Ja/MsCamqc7mkt35aA8DfrMjmfcfS9kdQFp2CEldcC5Fr9YlomiOus7vtagWmEBFr4 iM9EpdWQVpohyX2zCms8RC5amzFmKlnKUXmZrOeiNFUIhGFu5JL1QaykxxJiTTyYjwT5 Jz+bSx32mO0wp6n0I8pXJYgNA7KIvGpauqMIca2y0atixsSc2TAEKxYHfcSh+akwjYRJ tzZjXcthh1yNHmFfIAYukfJcoHYdLRVglOJf/oyqCvxjq+7HT9/v8U5cSLyWjORkbXez hVchyCpCAlCfq7Uhdr16N4OSMPAGdvH4hYzmENrxn/UbcXPEooAtzXmX09AcoNy1ocCq 33yw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id r73-v6si2563319pfk.83.2018.07.17.21.10.50; Tue, 17 Jul 2018 21:11:21 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726251AbeGREpo (ORCPT + 99 others); Wed, 18 Jul 2018 00:45:44 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:56850 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726068AbeGREpo (ORCPT ); Wed, 18 Jul 2018 00:45:44 -0400 Received: from localhost (unknown [172.58.43.84]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 5A28F100851F1; Tue, 17 Jul 2018 21:09:53 -0700 (PDT) Date: Wed, 18 Jul 2018 13:09:52 +0900 (KST) Message-Id: <20180718.130952.1583275621144007884.davem@davemloft.net> To: mst@redhat.com Cc: jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, wexu@redhat.com, jfreimann@redhat.com, tiwei.bie@intel.com, maxime.coquelin@redhat.com Subject: Re: [PATCH net-next V2 0/8] Packed virtqueue support for vhost From: David Miller In-Reply-To: <20180716154102-mutt-send-email-mst@kernel.org> References: <20180716113720-mutt-send-email-mst@kernel.org> <33f4643f-f226-0389-1f4f-607c289db94e@redhat.com> <20180716154102-mutt-send-email-mst@kernel.org> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 17 Jul 2018 21:09:54 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Michael S. Tsirkin" Date: Mon, 16 Jul 2018 15:49:04 +0300 > I'm not sure I understand this approach. Packed ring is just an > optimization. What value is there in merging it if it does not help > speed? So it seems that both Tiwei's and Jason's packed patch sets are kind of in limbo due to this discussion. If I understand Jason correctly, he's trying to say that although this work doesn't show improvements by itself, however it paves the way such that optimizaations done in the future will be more visible. I kind of can see Michael's viewpoint too, in that we should put this stuff in later when it does actually show some difference. Therefore, I'll mark both patch sets as "deferred" for now. Let me know if I should do something else. Thanks!