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=-1.1 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 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 7C768C433DF for ; Mon, 22 Jun 2020 10:45:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51C7A206F1 for ; Mon, 22 Jun 2020 10:45:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OUtwn2A8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727836AbgFVKpA (ORCPT ); Mon, 22 Jun 2020 06:45:00 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:59173 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726919AbgFVKo7 (ORCPT ); Mon, 22 Jun 2020 06:44:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592822697; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bd6LBfF9XDzhgzHssZPSe+Lg08kndjqNduL115ZBJfw=; b=OUtwn2A8AKlen5Py0TTiKV8rDITUrAP3LgQJQWn2sjtsEIScpICL8oWCifQK0QGeQ7VL2s is4b6aHLwk9LBVNWnNjLSGqYn+o0A5PfDgheUuSPF1gDaMX21eqeuRkyLHou6EFLf5vEdb AQ1DkvVMn5odd6NT/Uh5zI9or5nhQq4= Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-12-C9mPxLFGMlmXkgHNwDcgZw-1; Mon, 22 Jun 2020 06:44:54 -0400 X-MC-Unique: C9mPxLFGMlmXkgHNwDcgZw-1 Received: by mail-qk1-f200.google.com with SMTP id i62so3336657qkd.18 for ; Mon, 22 Jun 2020 03:44:54 -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:content-transfer-encoding; bh=bd6LBfF9XDzhgzHssZPSe+Lg08kndjqNduL115ZBJfw=; b=nj5lRJ/c72ZsQH/zwp6ZVumQprByKxL3NxSQHuFDIaDfchkENTw+zc60VsHpkWzMCW 7Y1web5kRCVj8UhPe0EXzUzhBFQRFxeSGueIPaRw0TMFSCl2oz8rYbzjVGGQEHp+QdlS soulb3L436kOA4NreROTMPTfJ8q7KV/D244IH8oe5FrURPEU1UuxxSX1Isc/y3LaI11C EtLt+y6ue6PCW1Otu+zuH+0W9SnkXHoHncXP6j7vKYXDRZElkU9HgiZZTDhqCatkyyeq ZOLhjqcIEk8znPSkLdZ1ZYPQrC5IE23dR8TzikWZaAwlwBdTthwaJqxjbw8Mp2aVF2pB Aj5A== X-Gm-Message-State: AOAM530jnh+GYi2UcM9p7jHxWnD8yJUFfv0Au9AsQcKIZkiyrgwstM6w 0h1BESGaWIZE7FwryzBzjsqeujTLZi2bK7509u/NDSsRu9TIOV0kjmLzCcZcJcaz6Nwrj1CtkbB 6KbNKSSJmCLHb+dC5ZaxKjEupgibLAKJlUMjg1mee X-Received: by 2002:a37:65cc:: with SMTP id z195mr3486052qkb.89.1592822694164; Mon, 22 Jun 2020 03:44:54 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyvnEcVAiDygOEo8OJvdbTYJXbYK5OuvbLC8XhYldjJDXeH7okBCt6wSTRbluvWc7hxWfBdRNbg+6gCp7JsIUc= X-Received: by 2002:a37:65cc:: with SMTP id z195mr3486036qkb.89.1592822693924; Mon, 22 Jun 2020 03:44:53 -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: Mon, 22 Jun 2020 12:44:17 +0200 Message-ID: Subject: Re: [PATCH RFC v8 02/11] vhost: use batched get_vq_desc version To: Jason Wang Cc: Konrad Rzeszutek Wilk , "Michael S. Tsirkin" , linux-kernel@vger.kernel.org, kvm list , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 22, 2020 at 11:07 AM Jason Wang wrote: > > > On 2020/6/20 =E4=B8=8A=E5=8D=882:07, Eugenio Perez Martin wrote: > > 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 differe= nt: > > * 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 > > > Which direction did you mean here? Guest TX or RX? Hi Jason. For both I created a linux bridge in the host, attach two guest interfaces with vhost-net, and make the netperf run on them. > > > > - TCP_RR from 6223.64 transactions/sec to 5739.44 > > > Perf diff might help. I think we can start from the RR result which > should be easier. Maybe you can test it for each patch then you may see > which patch is the source of the regression. > Ok, I will look for differences. Thanks! > Thanks >