From owner-freebsd-hackers@freebsd.org Thu Apr 19 20:59:42 2018 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 37BDAFA1FF7 for ; Thu, 19 Apr 2018 20:59:42 +0000 (UTC) (envelope-from 01000162dfb48d86-02daee46-919a-4193-84d2-5352d6b05107-000000@amazonses.com) Received: from a8-52.smtp-out.amazonses.com (a8-52.smtp-out.amazonses.com [54.240.8.52]) (using TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id CF24C7E38C for ; Thu, 19 Apr 2018 20:59:41 +0000 (UTC) (envelope-from 01000162dfb48d86-02daee46-919a-4193-84d2-5352d6b05107-000000@amazonses.com) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=dqtolf56kk3wpt62c3jnwboqvr7iedax; d=tarsnap.com; t=1524171574; h=Subject:To:Cc:References:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding; bh=sgYZbLcbH3RnOJ2m++LL95Kme2tsNLsEp8uETz2uhsQ=; b=ejVXxH5jnHbLpJHlLis0mAybs37tjTFNy766MRVpyfF8sKu2G84UUL/E/sXuCUZ2 Cc2aYkPDNFsCR8nRF3pfxFmdQ9jBfxqzg7cHiHH11Vo8d55S+3QYu/VuMgfDYORpj8n gzt6AmcVnz3dqjbUILX4WmYat8xoK9x8uPBL2T3A= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=ug7nbtf4gccmlpwj322ax3p6ow6yfsug; d=amazonses.com; t=1524171574; h=Subject:To:Cc:References:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding:Feedback-ID; bh=sgYZbLcbH3RnOJ2m++LL95Kme2tsNLsEp8uETz2uhsQ=; b=e1WcsCScHnkKqICfmaoP+i4YYdgfXOA+HuN5DGKY0rFzGQDZwJBHcBFEssRZz1BG +ZyRQgtNLg52DFABwdgw5IJd4aMeR7kQr/DYW8ziSZxMS5GX60FnYQD+zeNL0B3kQG0 ofdp1cw0AvLOkxdAq6kauP5/S3+yY/acAFptjR9I= Subject: Re: RFC: Hiding per-CPU kernel output behind bootverbose To: Konstantin Belousov Cc: freebsd-hackers@freebsd.org References: <01000162df15f856-1e5d2641-2a72-4250-8d8e-adcd47bc5db4-000000@email.amazonses.com> <20180419204405.GE6887@kib.kiev.ua> From: Colin Percival Openpgp: preference=signencrypt Autocrypt: addr=cperciva@tarsnap.com; prefer-encrypt=mutual; keydata= xsDhBElrAAcRBACDfDys4ZtK+ErCJ1HAzYeteKpm3OEsvT/49AjUTLihkF79HhIKrCQU+1KC zv7BwHCMLb6hq30As9L7iFKG7n5QFLFC4Te/VcITUnWHMG/c3ViLOfJGvi+9/nOEHaM1dVJY D6tEp5yM1nHmVQpo9932j4KGuGFR0LhOK5IHXOSfGwCgxSFDPdgxe2OEjWxjGgY+oV3EafcD +JROXCTjlcQiG/OguQH4Vks3mhHfFnEppLxTkDuYgHZQiUtpcT9ssH5khgqoTyMar05OUdAj ZIhNbWDh4LgTj+7ZmvLhXT5Zxw8LX9d7T36aTB8XDQSenDqEtinMWOb0TCBBLbsB8EFG1WTT ESbZci9jJS5yhtktuZoY/eM8uXMD/3k4FWFO80VRRkELSp+XSy/VlSQjyi/rhl2nQq/oOA9F oJbDaB0yq9VNhxP+uFBzBWSqeIX0t1ZWLtNfVFr4TRP5hihI5ICrg/0OpqgisKsU2NFe9xyO hyJLYmfD8ebpDJ/9k30C7Iju9pVrwLm1QgS4S2fqJRcR+U4WbjvP7CgSzSVDb2xpbiBQZXJj aXZhbCA8Y3BlcmNpdmFAdGFyc25hcC5jb20+wmEEExECACEFAklrALYCGwMHCwkIBwMCAQQV AggDBBYCAwECHgECF4AACgkQOM7KaQxqam6/igCgn+z2k3V5ggNppmWrZstt1U2lugsAoL7L wS9V9yLtil3oWmHtwpUqYruEzsFNBElrAAcQCAD3ZLMIsP4CIDoJORg+YY0lqLVBgcnF7pFb 4Uy2+KvdWofN+DKH61rZLjgXXkNE9M4EQC1B4lGttBP8IY2gs41y3AUogGdyFbidq99rCBz7 LTsgARHwFxZoaHmXyiZLEU1QZuMqwPZV1mCviRhN5E3rRqYNXVcrnXAAuhBpvNyj/ntHvcDN 2/m+ochiuBYueU4kX3lHya7sOj+mTsndcWmQ9soOUyr8O0r/BG088bMn4qqtUw4dl5/pglXk jbl7uOOPinKf0WVd2r6M0wLPJCD4NPHrCWRLLLAjwfjrtoSRvXxDbXhCdgGBa72+K8eYLzVs hgq7tJOoBWzjVK6XRxR7AAMGB/9Mo3iJ2DxqDecd02KCB5BsFDICbJGhPltU7FwrtbC7djSb XUrwsEVLHi4st4cbdGNCWCrp0BRezXZKohKnNAPFOTK++ZfgeKxrV2sJod+Q9RILF86tQ4XF 7A7Yme5hy92t/WgiU4vc/fWbgP8gV/19f8nunaT2E9NSa70mZFjZNu4iuwThoUUO5CV3Wo0Y UISsnRK8XD1+LR3A2qVyLiFRwh/miC1hgLFCTGCQ3GLxZeZzIpYSlGdQJ0L5lixW5ZQD9r1I 8i/8zhE6qRFAM0upUMI3Gt1Oq2w03DiXrZU0Fu/R8Rm8rlnkQKA+95mRTUq1xL5P5NZIi4gJ Z569OPMFwkkEGBECAAkFAklrAAcCGwwACgkQOM7KaQxqam41igCfbaldnFTu5uAdrnrghESv EI3CAo8AoLkNMks1pThl2BJNRm4CtTK9xZeH Message-ID: <01000162dfb48d86-02daee46-919a-4193-84d2-5352d6b05107-000000@email.amazonses.com> Date: Thu, 19 Apr 2018 20:59:34 +0000 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180419204405.GE6887@kib.kiev.ua> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SES-Outgoing: 2018.04.19-54.240.8.52 Feedback-ID: 1.us-east-1.Lv9FVjaNvvR5llaqfLoOVbo2VxOELl7cjN0AOyXnPlk=:AmazonSES X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 19 Apr 2018 20:59:42 -0000 On 04/19/18 13:44, Konstantin Belousov wrote: > On Thu, Apr 19, 2018 at 06:06:21PM +0000, Colin Percival wrote: >> On large systems (e.g., EC2's x1e.32xlarge instance type, with 128 vCPUs) >> the boot time console output contains a large number of lines of the forms >> >> SMP: AP CPU #N Launched! >> cpuN: on acpi0 >> estN: on cpuN >> >> Having 128 almost-identical lines of output doesn't seem very useful, and >> it actually has a nontrivial impact on the time spent booting. >> >> Does anyone mind if I hide these by default, having them only show up if >> boot verbosity is requested? > > The 'CPU XX Launched' messages are very useful for initial diagnostic > of the SMP startup failures. You need to enable bootverbose to see the > hang details, but for initial hint they are required. Unfortunately, AP > startup hangs occur too often to pretend that this can be delegated to > very specific circumstances. Do SMP startup failures need to be debugged often enough to justify having this verbosity every time a FreeBSD system boots? > Rest of the lines you pasted are normal device attach messages, so it is > not clear how would you hide them without ugly hacks. I would be willing to employ ugly hacks in order to silence unhelpful output and speed up the boot process. -- Colin Percival Security Officer Emeritus, FreeBSD | The power to serve Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid