From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77FF5C433DF for ; Fri, 19 Jun 2020 18:08:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5719220DD4 for ; Fri, 19 Jun 2020 18:08:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cl1+652e" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403967AbgFSSIo (ORCPT ); Fri, 19 Jun 2020 14:08:44 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:50122 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388336AbgFSSIl (ORCPT ); Fri, 19 Jun 2020 14:08:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592590119; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=M1kqnSC0TnwwjU9pqdl+Jl6MnsvVIxbg1NKgAjCQLQk=; b=cl1+652e+fWCtGoesj6yht07XsNuGao/aRLVpVL6aYALBdFfI2CtzuMyey99gio5cwLa4A sj984r2RhF0u20QEphNqsM7xwo6pKjNhqxxrRdHqfj6/ilQswT2hXx1aycFGVmIx0Gdn4m eevFSxmtm36zvY0BFfoaqZqCvbgP8kc= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-376-P2k-mjZgNmOkJ-8It2sQyA-1; Fri, 19 Jun 2020 14:08:34 -0400 X-MC-Unique: P2k-mjZgNmOkJ-8It2sQyA-1 Received: by mail-qv1-f70.google.com with SMTP id h4so7401105qvr.21 for ; Fri, 19 Jun 2020 11:08:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=M1kqnSC0TnwwjU9pqdl+Jl6MnsvVIxbg1NKgAjCQLQk=; b=EkSPCrvAph3eu8OAnZG3sxGWFe6Ue2ei5Ki0COQxfgXg0Zlt9XZ0v4MkntpEWnuVtD F/OvsiR6YlzmFHvjQLFF1w0JvtINLZnOMP2fhIoR0nSRkQBLz3tBo5hP+LnIKO+20cKM QMLr5cAtNfnZhneFMdO+92rV47QKJAIUvS/4dlV4cidXuLNWobckcOsrZzxgZpG/dDfD 2wYY9NSPGD2SY1ovUetXqOyvpXjM4tJ5IWNhS9rSJQcrX2y0CoJjVG+98Z8+mfSUrKmP far6jGZ//s6KFHDej9La0MMJewfX4bAaHVnYooD2RmvdmYveIrHBuTTFqZgGh9ijc8oW He1A== X-Gm-Message-State: AOAM530cClGqD6dNz4kcBXaPGtuTTAZa4Eei7gLGbbqeqTD4gVp6CSWU 1bCOfa8rSafd3sZoUmaPiZECJmjDqQC+TAWsGnu82DFXW8wEAx4rCJG/xc/V+xgNXYd21vBMs4o PyMllMTeDa1bYEXiVc52JYw+B+osHggBCvLJfjVxB X-Received: by 2002:aed:2171:: with SMTP id 104mr2269424qtc.22.1592590114086; Fri, 19 Jun 2020 11:08:34 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxb3LLfD5Gk7BoQBiwyBzy1qquwOQYCpCWEpfsWGm3cQ1kfZddE50/+gf0EU9STwwFtmiZcEeywa03jj7Vwsy0= X-Received: by 2002:aed:2171:: with SMTP id 104mr2269401qtc.22.1592590113830; Fri, 19 Jun 2020 11:08:33 -0700 (PDT) MIME-Version: 1.0 References: <20200611113404.17810-1-mst@redhat.com> <20200611113404.17810-3-mst@redhat.com> <20200611152257.GA1798@char.us.oracle.com> In-Reply-To: From: Eugenio Perez Martin Date: Fri, 19 Jun 2020 20:07:57 +0200 Message-ID: Subject: Re: [PATCH RFC v8 02/11] vhost: use batched get_vq_desc version To: Konrad Rzeszutek Wilk Cc: "Michael S. Tsirkin" , linux-kernel@vger.kernel.org, kvm list , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 15, 2020 at 2:28 PM Eugenio Perez Martin wrote: > > On Thu, Jun 11, 2020 at 5:22 PM Konrad Rzeszutek Wilk > wrote: > > > > On Thu, Jun 11, 2020 at 07:34:19AM -0400, Michael S. Tsirkin wrote: > > > As testing shows no performance change, switch to that now. > > > > What kind of testing? 100GiB? Low latency? > > > > Hi Konrad. > > I tested this version of the patch: > https://lkml.org/lkml/2019/10/13/42 > > It was tested for throughput with DPDK's testpmd (as described in > http://doc.dpdk.org/guides/howto/virtio_user_as_exceptional_path.html) > and kernel pktgen. No latency tests were performed by me. Maybe it is > interesting to perform a latency test or just a different set of tests > over a recent version. > > Thanks! I have repeated the tests with v9, and results are a little bit different: * If I test opening it with testpmd, I see no change between versions * If I forward packets between two vhost-net interfaces in the guest using a linux bridge in the host: - netperf UDP_STREAM shows a performance increase of 1.8, almost doubling performance. This gets lower as frame size increase. - rests of the test goes noticeably worse: UDP_RR goes from ~6347 transactions/sec to 5830 - TCP_STREAM goes from ~10.7 gbps to ~7Gbps - TCP_RR from 6223.64 transactions/sec to 5739.44