From nobody Wed Nov 10 17:39:04 2021 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 087EE183A1CC; Wed, 10 Nov 2021 17:39:15 +0000 (UTC) (envelope-from bzeeb-lists@lists.zabbadoz.net) Received: from mx1.sbone.de (mx1.sbone.de [IPv6:2a01:4f8:13b:39f::9f:25]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mx1.sbone.de", Issuer "SBone.DE" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4HqBtB5h1Fz4VZX; Wed, 10 Nov 2021 17:39:14 +0000 (UTC) (envelope-from bzeeb-lists@lists.zabbadoz.net) Received: from mail.sbone.de (mail.sbone.de [IPv6:fde9:577b:c1a9:31::2013:587]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mx1.sbone.de (Postfix) with ESMTPS id 607708D4A215; Wed, 10 Nov 2021 17:39:07 +0000 (UTC) Received: from content-filter.sbone.de (content-filter.sbone.de [IPv6:fde9:577b:c1a9:31::2013:2742]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.sbone.de (Postfix) with ESMTPS id 9569BE7085A; Wed, 10 Nov 2021 17:39:06 +0000 (UTC) X-Virus-Scanned: amavisd-new at sbone.de Received: from mail.sbone.de ([IPv6:fde9:577b:c1a9:31::2013:587]) by content-filter.sbone.de (content-filter.sbone.de [fde9:577b:c1a9:31::2013:2742]) (amavisd-new, port 10024) with ESMTP id 1nLPHeTR9ZeT; Wed, 10 Nov 2021 17:39:05 +0000 (UTC) Received: from [192.168.2.110] (unknown [IPv6:fde9:577b:c1a9:31:147a:793a:fa30:961]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.sbone.de (Postfix) with ESMTPSA id 4E2E1E70814; Wed, 10 Nov 2021 17:39:05 +0000 (UTC) From: "Bjoern A. Zeeb" To: "Mitchell Horne" Cc: freebsd-arch@freebsd.org, freebsd-hackers@freebsd.org, cperciva@freebsd.org Subject: Re: A new boot-time trace framework Date: Wed, 10 Nov 2021 17:39:04 +0000 X-Mailer: MailMate (2.0BETAr6151) Message-ID: <5E5F06E4-F0FA-45F9-B121-88C69CA15A25@lists.zabbadoz.net> In-Reply-To: References: List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 4HqBtB5h1Fz4VZX X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] X-ThisMailContainsUnwantedMimeParts: N On 10 Nov 2021, at 16:26, Mitchell Horne wrote: > Unlike TSLOG, I intend for this work to be compiled in to the kernel > by default, but disabled behind a tunable (kern.boottrace.enabled). > The cost of doing so should be minimal, only a couple of syscalls > added to init(8) at most. I think if you really want to have this on by default (whether that make sense or not for the majority of people) I’d at least avoid the function call and reduce it to a branch which is super-easy to do. My honest feeling is that another of the at least 3 other tracing mechanisms existing these days be better extended and improved rather than another one added; we were always joking about 3 firewalls but if we keep going this path we can soon start joking about 9 tracing mechanisms and that will be a major mess for sysadmins. I can see from when this work was coming and back then it might have made sense this way; but more than a decade has passed.. /bz