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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 CCA77C47254 for ; Tue, 5 May 2020 08:46:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F75620675 for ; Tue, 5 May 2020 08:46:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="unknown key version" (0-bit key) header.d=tlapnet.cz header.i=@tlapnet.cz header.b="W3X8sF9i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728402AbgEEIqT (ORCPT ); Tue, 5 May 2020 04:46:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53674 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728341AbgEEIqT (ORCPT ); Tue, 5 May 2020 04:46:19 -0400 Received: from mail-qk1-x72f.google.com (mail-qk1-x72f.google.com [IPv6:2607:f8b0:4864:20::72f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92922C061A0F for ; Tue, 5 May 2020 01:46:18 -0700 (PDT) Received: by mail-qk1-x72f.google.com with SMTP id i14so1481249qka.10 for ; Tue, 05 May 2020 01:46:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tlapnet.cz; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=sfUjy8na400+ow1P9rnl6ZQG3r/B8w9L9NIvN0XlX3E=; b=W3X8sF9iVciApUpFnQwQOt4GQMuJVVgzrEiLdKpUaL8G5sky4aVvbLYSvMB5bD+R1n wBWsGf6ekPI9v7+uwArqoS65b8Am88ktsjvGmoPVCrsWC/mv2pQwjlZW/QjcrVKwdoAh D1SpVMv7qsML9E1afdy5a3V5RFbyxq+8dbOqosDYgwwBL0avFhmklFyZPAszI24rW0C7 TKuwWqbzZlljywYVLJ0+Km1uliaJbtjOr174Qf7/Mzvg/vkIB2oKEgqgQUdk7xPZDoo0 vyHUtL8Sr+DwAaoN9QGJb9jNRqHIRYyoWX/oCfdAsY4qaEj2tsMt71d4d3wonDzdTOu7 KhIA== 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=sfUjy8na400+ow1P9rnl6ZQG3r/B8w9L9NIvN0XlX3E=; b=P1+maeyHokLlYOCfG53cIbsGHLYXvPILYDbKnNgWVO8lZa4hrmoPZMfY5tJp9zYI5K kcUA4I+Bg5TQ3WBxuDJmMVPmmvr2OM6Bs5BkvF/Z7szvJGY9kNa77iUMygm/JE9fS9sS k6bZSnDfiZBrvYsV6j0z9+dg9l89+JT1Aal1Qz0C13iNcy6/JWNd4zIxvSOZaajtMJaj 1AbztJ5l1ErxKVbFy26VC/9OuxRd2AqI7vMAm0+TzYCqgn9Fl6QI7yTGs3RHUVeJU3bB 99rG/oloc4zte3eVfONorqDi42xnbjh+flTk1fcVNup2opMobuKwI3h+MaAcrCiOYYvD yZIw== X-Gm-Message-State: AGi0PuYuhZQ0jD2TLquUAEBO07t89Qk72Gyqp3Ajt08B/6U9IIO55fJ0 JCgOZb19Q+TBfOgL993Wc7ALf6RquZSfWI93tyRGng== X-Google-Smtp-Source: APiQypK06+lny+eL5ornYkOtl5hsjdq9ICetvA7vNWCf18gfZcKsZH1zv2tjFPOWvv5KRZleUSsue1DduSTWrTdmGSc= X-Received: by 2002:a37:e214:: with SMTP id g20mr2316487qki.374.1588668376651; Tue, 05 May 2020 01:46:16 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: =?UTF-8?Q?V=C3=A1clav_Zindulka?= Date: Tue, 5 May 2020 10:46:05 +0200 Message-ID: Subject: Re: iproute2: tc deletion freezes whole server To: Cong Wang Cc: Linux Kernel Network Developers Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, May 4, 2020 at 7:46 PM Cong Wang wrote: > > Sorry for the delay. I lost connection to my dev machine, I am trying > to setup this on my own laptop. Sorry to hear that. I will gladly give you access to my testing machine where all this nasty stuff happens every time so you can test it in place. You can try everything there and have online results. I can give you access even to the IPMI console so you can switch the kernel during boot easily. I didn't notice this problem until the time of deployment. My prior testing machines were with metallic ethernet ports only so I didn't know about those problems earlier. > On Mon, May 4, 2020 at 10:36 PM Cong Wang wrote: > > > > Regarding to your test result above, I think I saw some difference > > on my side, I have no idea why you didn't see any difference. Please > > let me collect the data once I setup the test environment shortly today. I saw some improvement too. It was more than 1.5s faster. Yet it was still over 21s. I measured it with perf trace, not with time. I'll try it the same way as you did. > > I tried to emulate your test case in my VM, here is the script I use: > > ==== > ip li set dev dummy0 up > tc qd add dev dummy0 root handle 1: htb default 1 > for i in `seq 1 1000` > do > tc class add dev dummy0 parent 1:0 classid 1:$i htb rate 1mbit ceil 1.5mbit > tc qd add dev dummy0 parent 1:$i fq_codel > done > > time tc qd del dev dummy0 root > ==== > > And this is the result: > > Before my patch: > real 0m0.488s > user 0m0.000s > sys 0m0.325s > > After my patch: > real 0m0.180s > user 0m0.000s > sys 0m0.132s My results with your test script. before patch: /usr/bin/time -p tc qdisc del dev enp1s0f0 root real 1.63 user 0.00 sys 1.63 after patch: /usr/bin/time -p tc qdisc del dev enp1s0f0 root real 1.55 user 0.00 sys 1.54 > This is an obvious improvement, so I have no idea why you didn't > catch any difference. We use hfsc instead of htb. I don't know whether it may cause any difference. I can provide you with my test scripts if necessary. Thank you.