From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.comp.sysutils.supervision.general/2437 Path: news.gmane.org!.POSTED!not-for-mail From: Steve Litt Newsgroups: gmane.comp.sysutils.supervision.general Subject: Can s6 be enough?: was s6-ps Date: Sat, 5 Jan 2019 15:30:28 -0500 Message-ID: <20190105153028.28bc0bab@mydesk.domain.cxm> References: <9f647c4c-2dc3-b977-928c-ee164ba88afe@ntlworld.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1546720107 20691 195.159.176.226 (5 Jan 2019 20:28:27 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 5 Jan 2019 20:28:27 +0000 (UTC) To: supervision@list.skarnet.org Original-X-From: supervision-return-2027-gcsg-supervision=m.gmane.org@list.skarnet.org Sat Jan 05 21:28:23 2019 Return-path: Envelope-to: gcsg-supervision@m.gmane.org Original-Received: from alyss.skarnet.org ([95.142.172.232]) by blaine.gmane.org with smtp (Exim 4.84_2) (envelope-from ) id 1gfsYR-0005Ha-9n for gcsg-supervision@m.gmane.org; Sat, 05 Jan 2019 21:28:23 +0100 Original-Received: (qmail 30403 invoked by uid 89); 5 Jan 2019 20:30:59 -0000 Mailing-List: contact supervision-help@list.skarnet.org; run by ezmlm Original-Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 30396 invoked from network); 5 Jan 2019 20:30:58 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; h=X-Originating-IP:Date:From:To:Subject:Message-ID:In-Reply-To:References:X-Mailer:MIME-Version:Content-Type:Content-Transfer-Encoding; s=default; d=troubleshooters.com; b=GM5XNGTIFa123ykCJF+zusm4RicR2B2wF+0ZiWKhytV0VhbA7sDp0WYVYiI0tk6dYk2rjDrXdO1t44guXAfYSTUHcj1cwLZKnj00f8FdUyy9FYET+xZOw4zldjaSPvyegQpun3GGIQbYY81/NreknoG18aHPoVfTreUXrbah8fo=; DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/simple; d=troubleshooters.com; s=default; t=1546720229; bh=AZ8MYXFciTm+kC2Tk/BE2/pZZu4=; l=2299; h=X-Originating-IP:Date:From:To:Subject:Message-ID:In-Reply-To: References:X-Mailer:MIME-Version:Content-Type: Content-Transfer-Encoding; b=FpQLB8GQxnkYIMHhSkq5j0SBRwM9CsBK9sOqYHIKH+8cIvt6kd7GFkclVsh+xQ9JC hB3pOBCMHwvWN2ChWJ4efF7V4cRDcmi4XPvuv/Fetxa1vzQuSGZ9Y0OQK2LSPIhyIt uN2ymmOkdzis852XmTHVk9bn+lW0qA287gFTSqVk= X-Originating-IP: [72.188.224.222] In-Reply-To: X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-unknown-linux-gnu) Xref: news.gmane.org gmane.comp.sysutils.supervision.general:2437 Archived-At: On Sat, 5 Jan 2019 10:46:29 +0000 Jonathan de Boyne Pollard wrote: > s6 and s6-rc are actually ports/packages in FreeBSD and s6 is a > package in Debian. Alas, the Debian world has not yet caught up with > the other toolsets, and the third-party Debian packaging for > s6-linux-utils and the others has yet to make it into Debian's own > repository. This brings up a question I've had for a long time. Three years ago I constructed an init consisting of Suckless Init as PID1 and s6 as the supervisor, which was called at the end of a simple rc file forked by Suckless Init. It worked just fine, without s6-rc or any other s6 products. =46rom discussions with Laurent I got the idea that the main added functionalities of s6-rc are: 1) Process ordering during boot 2) Ability to intermix longruns with oneshots Everybody appreciates the preceding two features, but personally, I don't think they're absolutely necessary. Runit has neither, yet it works just fine for most things. When I first switched to runit, with its indeterminate ordering, I figured that with the dependencies I built into the run scripts, boot would resemble a field of mousetraps throwing ping pong balls. But that wasn't the case: runit brought everything up quickly and without trouble. So I'm thinking that although process ordering and intermixing are features we'd everyone likes, all but the most discerning among us could get along without them and therefore init with s6 alone. This is more than theoretical. As you remember, Debian's runit package manager wrote to ask about a minor problem with too many .u files and was contemplating changing some code, but nobody knew the code intimately, and runit is pretty much unmaintained at this point. So I suggested s6, which apparently has a Debian package but not one for s6-rc. My opinion is one can boot just fine with s6 alone, as long as you're willing to forego startup ordering and intermixing of longruns and oneshots, which by definition a runit fan is. So what do you all think? Is s6 a useful init system without s6-rc? Thanks, =20 SteveT Steve Litt=20 January 2019 featured book: Troubleshooting: Just the Facts http://www.troubleshooters.com/tjust