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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 C79FCC43387 for ; Tue, 18 Dec 2018 11:17:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96AC321850 for ; Tue, 18 Dec 2018 11:17:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="W+q4GS5g" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726588AbeLRLRH (ORCPT ); Tue, 18 Dec 2018 06:17:07 -0500 Received: from mail-pl1-f178.google.com ([209.85.214.178]:37990 "EHLO mail-pl1-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726370AbeLRLRG (ORCPT ); Tue, 18 Dec 2018 06:17:06 -0500 Received: by mail-pl1-f178.google.com with SMTP id e5so7690207plb.5 for ; Tue, 18 Dec 2018 03:17:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=AAhV60gjLPi+uPXQSvPbLAB0Ic18RRXevOb0ibYLBjQ=; b=W+q4GS5gszUcBrFh7f1l5k5JJAPVXrK7tML5+W3KwEAqgsP7tux3ciRbVoqc5S9WlO 45/rs359P+mL3i6XkQq3rq/2pBDjP+ZK3Uweu0dHIwHElhWVJ2bpO0vTXjlICLsdaJO/ 5EwaR9hcf5CPYb2mbsZ6EgRuU76IkKqSG1zMvMF/M9ZXpf0GSA7NPcQcHg39yhCEsUQs +qDL8wXMPBTmFqznqJDLBc7ANnA+WW72PykaRt/ViLSv2mqygo8R1RKgCfZlRfxIy2xK nxFlIojL4uOw754wdpCTWe5gvDXjZ6cKJd1yjYaogKoV+d9qeZoeEGGuDo64Bn6ItQVY RIRw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=AAhV60gjLPi+uPXQSvPbLAB0Ic18RRXevOb0ibYLBjQ=; b=byLd7o8XXvhuFjEpEiQCqlTmo+IEWJOd+XvD5oHhYTfBlpbjZw3wog5J6CdBsueHDn tGSadbuiUjcyr2W/Dmh+26QnlmGmWMboWwl24xmBxZS5WpwAzLBcbWspd57DUEA+iTGV L9v6+0Q5XI0A5w8yNpuBkvwlvw1EE0S2YzbVySADZ9wIOMIGbVC3Nsen8YJKaENpRU9O TEqqvOKwoXeK6r5qnajT6X/58eF0hdYiVdh2cK9XAx9gJATdciwd/kaA7Xm7c6WxkroW 84xFs36Mvv3X1bhkqjQzaS90Attb0pivGZdRwQPNNivrX5OIJ+Xw3y/FGzBJExOerrwM j2kw== X-Gm-Message-State: AA+aEWa5ikqcBoFZSM81vi+I2uJhIzlehBUs9/9f/cjDsCzVlLS1S5TO xjJrrqD/u259gwL3EoCkhIY= X-Google-Smtp-Source: AFSGD/WanpjJYcY0PCeJzE5TmC8T623oZd2UUXoyhzqvL26VoSPOhuTq+ldvNBx9l29snpZdcXD5Og== X-Received: by 2002:a17:902:1127:: with SMTP id d36mr15544631pla.299.1545131825938; Tue, 18 Dec 2018 03:17:05 -0800 (PST) Received: from localhost ([175.223.2.245]) by smtp.gmail.com with ESMTPSA id p77sm29011960pfi.85.2018.12.18.03.17.04 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 18 Dec 2018 03:17:05 -0800 (PST) Date: Tue, 18 Dec 2018 20:17:01 +0900 From: Sergey Senozhatsky To: Peter Zijlstra Cc: Sergey Senozhatsky , Petr Mladek , Steven Rostedt , Borislav Petkov , Andrew Morton , linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: Re: [RFC][PATCH] printk: increase devkmsg write() ratelimit Message-ID: <20181218111701.GA32522@jagdpanzerIV> References: <20181218091842.4996-1-sergey.senozhatsky@gmail.com> <20181218104812.GC15430@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181218104812.GC15430@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.11.1 (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (12/18/18 11:48), Peter Zijlstra wrote: > > I know that there is a "kernel.printk_devkmsg" interface; do we > > expect every systemd-enabled distro to find that out and to tweak > > kernel.printk_devkmsg or shall we change the default devkmsg > > ratelimit instead? > > How about we complain to systemd instead? We certainly can. As far as I understand, they log shutdown events (including errors and warnings): what they kill, what they stop, what they umount, etc. The more partitions, services are running (I guess), the more things they need to umount, kill, stop; hence, the more messages. I kinda can imagine what they will answer ;) The below (and a bunch of other) messages are getting ratelimited. I'm not sure what will happen should any of those steps fail and print warning-s. My guess would be that we probably can ratelimit those warnings: ... systemd[1]: Unmounting /home... systemd[1]: Unmounting Temporary Directory (/tmp)... systemd[1]: Unmounted Temporary Directory (/tmp). systemd[1]: Stopped target Swap. systemd[1]: Unmounted /boot. systemd[1]: Stopped File System Check on /dev/disk/by-uuid/a0737dff-e797-44f0-aea7-d0df1107ff63. systemd[1]: Stopped File System Check on /dev/disk/by-uuid/5d773b72-e200-4d11-a219-176d62a16d8d. systemd[1]: Unmounted /home. systemd[1]: Stopped File System Check on /dev/disk/by-uuid/35319ddc-9b92-4ab0-aaa4-9922db636a5e. systemd[1]: Unmounted /media/edev. systemd[1]: Stopped File System Check on /dev/disk/by-uuid/da00daaf-5601-4531-912e-bd69103b379d. systemd[1]: Unmounted /media/dump. systemd[1]: Reached target Unmount All Filesystems. systemd[1]: Stopped File System Check on /dev/disk/by-uuid/b52da2df-161b-4c33-b700-277d95b9672f. systemd[1]: Removed slice system-systemd\x2dfsck.slice. systemd[1]: Stopped target Local File Systems (Pre). systemd[1]: Stopped Create Static Device Nodes in /dev. systemd[1]: Stopped Create System Users. systemd[1]: Stopped Remount Root and Kernel File Systems. systemd[1]: Reached target Shutdown. systemd[1]: Reached target Final Step. systemd[1]: Starting Reboot... -ss