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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92259C77B71 for ; Tue, 18 Apr 2023 03:23:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229560AbjDRDX2 (ORCPT ); Mon, 17 Apr 2023 23:23:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229517AbjDRDX1 (ORCPT ); Mon, 17 Apr 2023 23:23:27 -0400 Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 778A51996 for ; Mon, 17 Apr 2023 20:23:25 -0700 (PDT) Received: by mail-ed1-x533.google.com with SMTP id 4fb4d7f45d1cf-506b2a08877so663863a12.2 for ; Mon, 17 Apr 2023 20:23:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vmn-com-au.20221208.gappssmtp.com; s=20221208; t=1681788204; x=1684380204; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=/O0ywaHNM2L+fze9eJoQ+O4a4k7b1EgMxTM8ShjvNyY=; b=3yKQTJVZIZzrT9z2t/OzQ3/kB902rV0r5KnF5f3etVTtiHEZ6Z6liwHKx5rbCJKoU2 RnW1vkS5MTpD7hlP36H7jdwQGz74eK/zLDaYzVJPxgYguGuRFNBbDh8Z8idtTUMY5lxS tjC6gJYe07MCcS+2F3AYS5h/whzyxcErqtH7cZngVS3PDiTJJkwJempvdrSowPO/RrNt ng83TPsoL71Wa3VEZq/AckzIHKsfqEgARbIqi9u+6VfD1L116Tk3bcBxHcKX432R0tXr N88wlXB1x2064K4XdVKZ7+76YPEbUmEBkDwHlIMRbEJ2pU5l6M2L0f4WlIS8NokEuzVF OoSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681788204; x=1684380204; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=/O0ywaHNM2L+fze9eJoQ+O4a4k7b1EgMxTM8ShjvNyY=; b=hiZNA59bTVEDMOxxFjIA1ym/18Yxdkx+1UOCfW9v2sHvJQYbuzJcMxpQ2j8QCpxMvE Bl2gOFpb9us/5QCCVfHIEHDyaPdh75azX5kuVheMIpARw1b4rDB0SXDyqbuE5316TMmr vWHt4vM8/l5CKRI9WizdlJKFoDmvVjvk75S9goDZ4926PlRmq82ymsnrvURsO0nhKLJ4 KT+5DHpjaIdEL2MpkRclYiw/l/CJFQPZyY+9XA6xX30lT7bSbr94k8bjScTrk1BCB3qO oB2OEqP9ifQqc5H2rVqlm5PAXZ7b6K1aHz4+nEvvwXOGJGnD8iHWqrJ2d4isBNyQJ/HL aIHg== X-Gm-Message-State: AAQBX9cZ//YVLVOVNkJHdnLu6XIOr6OT06gNxXG0qAxtkrmYGWquuzIN u+Sj0F9v48SkkZz7AIUtvQalUgvkAUIVKxPlkOe7S7rf8iSyldLG7Ts= X-Google-Smtp-Source: AKy350aejZo9bVuPbqnoN6kcFwFISH69nTub5h8M1F9dNftvmoEMeELck9DOFWNTfwgiK+MhHKTz5mIFhzd6mzCMqSU= X-Received: by 2002:aa7:d844:0:b0:506:8d8f:4715 with SMTP id f4-20020aa7d844000000b005068d8f4715mr839304eds.7.1681788203549; Mon, 17 Apr 2023 20:23:23 -0700 (PDT) MIME-Version: 1.0 From: Rod Webster Date: Tue, 18 Apr 2023 13:23:12 +1000 Message-ID: Subject: Excessive network latency when using Realtek R8168/R8111 et al NIC To: linux-rt-users@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org Hi guys, I hope this is the right place to report an issue We are linuxcnc users and as such we are long term users of PREEMPT_RT on x86 (and some other platforms) A number of PC's in use by our members have recently been experiencing excessive Real Time network latency since the 5.10 kernel and above. We are excited to see this seems to have been mostly resolved with the 6.3 kernel compiled from patched kernel.org source. But we are also experiencing excessive Real time network latency on some NIC hardware, mostly with Realtek NIC's in this list. https://www.realtek.com/en/component/zoo/category/network-interface-controllers-10-100-1000m-gigabit-ethernet-pci-express-software Many modern industrial PC's are using Realtek NIC drivers that cannot be changed out so this is a problem for us. It's our understanding that the R8169 kernel driver module should provide support for this hardware. It does indeed do this but real time network latency is unacceptable. Debian offers a R8168-dkms driver. I understand it is being deprecated in favor of the R8169 kernel module driver. Installing the R8168-dkms driver on the 6.3 kernel improves RT network latency/jitter by 400% over the R8169 driver. We are users not kernel developers. How can we escalate this issue so acceptable RT performance is restored? end -Regards -Rod Webster