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=-6.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 47C9DC433DF for ; Fri, 31 Jul 2020 01:22:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 244F921775 for ; Fri, 31 Jul 2020 01:22:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="J5qSEmko" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730926AbgGaBV6 (ORCPT ); Thu, 30 Jul 2020 21:21:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728262AbgGaBV5 (ORCPT ); Thu, 30 Jul 2020 21:21:57 -0400 Received: from mail-ot1-x343.google.com (mail-ot1-x343.google.com [IPv6:2607:f8b0:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF9FFC061574 for ; Thu, 30 Jul 2020 18:21:56 -0700 (PDT) Received: by mail-ot1-x343.google.com with SMTP id v21so14278326otj.9 for ; Thu, 30 Jul 2020 18:21:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=WhCSkMbJs+BIgp6gsZopFGoFqV6gwEHPHN197f+fHXw=; b=J5qSEmkoxPyRKsnwzDMkVy2jWwMJUfSbD8cEq3Qk+H5OHZTfEVpiBMc1Dora2PkQTt 3nA6g8XZVREicL4c+ym12YbHp/t5ZCQECm5BUQ4yxrQ6HGSb2YreWauJOlzwZmcg24HS 8GXvDZ0kGYdfeJq2zY+Tr57vuI2zHIUABrjGZp4nuAulzVukth4rBpe3VGD42kSO71jp ztNiQycHcIXzlmXHBnyYWa49oFYmVGfYyGrbQDKKZczaxzy4mC7gE0GsogHqw6zBCpr1 LHJX6UG5vcBeZsgB6an0ua/5b8WxokI+m7DbhlQa9ChbT6tQb6OLA2usMsjhdDNUjsTJ jXbQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=WhCSkMbJs+BIgp6gsZopFGoFqV6gwEHPHN197f+fHXw=; b=nm/Uo5rFdDfs16rS6zY7QwAFE8AFC92hJLonpKo5h5CcQVufA1RligBr8tiqMUqaK3 WKYKkvxqlbPzUdAp2UGpEYGt/BqVhsuPPb9pRrcmzrUtNV1Xu0xzqLjYq2Yu/xboH1sD NxNhAdPe6ACcfkd0Qt4pPHTVju0tdr6UV4AGnP7qgK4OLeSph19OfSrBTmBHQVPn3aW4 artdNkbfm2BqFMKnCoaQot0vCXmi2aE+MIvLhuDuskPpTzHjWvjGN7FSYKN4XXr22Jr8 L9zCgssADmWVPwOK+LLqGxE/l9V6sey6+3epn/VN/Zer6TEnZxmobLIvz0USxV3waxAP VAuA== X-Gm-Message-State: AOAM531hafes2k9MOTs8qxH1bOTPeSt5tVLSrWa/clp7MEzSrbsyYV+Z xbBorJ01XTK9X1JAFnh9IMM= X-Google-Smtp-Source: ABdhPJxXO+IkVsgpc+8vFcsgkgtc3AwIYa5p+xgFZ1TRYgAl0p+r15Jb6EiVFZcTXcFDcvFvlB6dfw== X-Received: by 2002:a05:6830:14d4:: with SMTP id t20mr1097641otq.166.1596158516190; Thu, 30 Jul 2020 18:21:56 -0700 (PDT) Received: from Davids-MacBook-Pro.local ([2601:284:8202:10b0:5917:9d89:e57d:b88d]) by smtp.googlemail.com with ESMTPSA id 92sm1124053otg.32.2020.07.30.18.21.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 30 Jul 2020 18:21:55 -0700 (PDT) Subject: Re: [PATCH 0/6] perf tools: Add wallclock time conversion support To: peterz@infradead.org, Jiri Olsa Cc: Arnaldo Carvalho de Melo , lkml , Ingo Molnar , Namhyung Kim , Alexander Shishkin , Michael Petlan , Ian Rogers , Andi Kleen , =?UTF-8?Q?Genevi=c3=a8ve_Bastien?= , Wang Nan , Jeremie Galarneau References: <20200730213950.1503773-1-jolsa@kernel.org> <20200730221423.GH2638@hirez.programming.kicks-ass.net> From: David Ahern Message-ID: Date: Thu, 30 Jul 2020 19:21:54 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200730221423.GH2638@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/30/20 4:14 PM, peterz@infradead.org wrote: > On Thu, Jul 30, 2020 at 11:39:44PM +0200, Jiri Olsa wrote: > >> The patchset is adding the ability to display TOD/wallclock timestamp >> in 'perf script' output and in 'perf data convert --to-ctf' subcommand, >> so the converted CTF data contain TOD/wallclock timestamps. > > But why? Wallclock is a horrible piece of crap. Why would you want to do > this? > Same reason I brought this up 9+ years ago: userspace lives on time-of-day, and troubleshooting is based on correlating timestamps from multiple sources. To correlate a perf event to syslog or an application log, we need time-of-day.