From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752144Ab0ENAD0 (ORCPT ); Thu, 13 May 2010 20:03:26 -0400 Received: from tango.0pointer.de ([85.214.72.216]:37410 "EHLO tango.0pointer.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751580Ab0ENADY (ORCPT ); Thu, 13 May 2010 20:03:24 -0400 Date: Fri, 14 May 2010 02:02:52 +0200 From: Lennart Poettering To: Peter Zijlstra Cc: Dhaval Giani , James Kosin , linux-kernel@vger.kernel.org, menage@google.com, balbir@linux.vnet.ibm.com, jsafrane@redhat.com, tglx@linutronix.de Subject: Re: [PATCH/RFC] Have sane default values for cpusets Message-ID: <20100514000252.GB30093@tango.0pointer.de> References: <4BEAB6FC.8090105@intcomgrp.com> <1273674048.1626.117.camel@laptop> <20100512190757.GA421@tango.0pointer.de> <1273755719.5605.3537.camel@twins> <20100513140354.GA12639@tango.0pointer.de> <1273785546.5605.3556.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1273785546.5605.3556.camel@twins> Organization: Red Hat, Inc. X-Campaign-1: () ASCII Ribbon Campaign X-Campaign-2: / Against HTML Email & vCards - Against Microsoft Attachments User-Agent: Leviathan/19.8.0 [zh] (Cray 3; I; Solaris 4.711; Console) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 13.05.10 23:19, Peter Zijlstra (peterz@infradead.org) wrote: > > On Thu, 2010-05-13 at 16:03 +0200, Lennart Poettering wrote: > > > On Wed, 2010-05-12 at 21:07 +0200, Lennart Poettering wrote: > > > > See Dhaval's patch on the background of systemd > > > > (http://0pointer.de/blog/projects/systemd.html). When a service is > > > > started in systemd, we create a cgroup for it, when it ends, we remove > > > > it. > > > > > > I seriously hope that's optional, because I for one would really hate a > > > system that does that. I still mostly build kernels with only cpuset in > > > and really don't want anybody but me creating groups in there. > > > > By default systemd will create its groups in the "debug" hierarchy, (at > > least for now, in the long run i'd like to see "noop" hierarchy or so, > > that doesn't sound so temporary), since that controller is not useful > > for anything but keeping track of processes. So it shouldn't bother you > > at all. > > Will it still work with a CONFIG_CGROUP=n kernel? I see distributions > deteriorate, you cannot even boot a raw bzImage kernel without initrd on > most distros (sure, its not too hard to fix, but still). No it won't work without cgroups. > Also, I get all kinds of dumb-ass init-script failures for not having > modules but stuff built-in. A prime example is NFS failing on start on > both fedora and ubuntu with a built-in nfs server (for different but > both retarded reasons). > > Requiring CONFIG_CGROUP=y to even get init running seems like a final > straw to ensure nobody will ever get anything to boot these days. Well, I wasn't aware that cgroups is now in the kernel for the purpose that people should *not* use it. Next time something is added to the kernel please mark it as "Hey, please don't use it, this is only here so that you don't use it. Thanks!" Maybe then dumb-ass folks like me will notice and refrain from using it. Requiring a single kernel options is not really too much to ask, is it? Don't be that conservative. systemd certainly won't require an initrd or anything else equally intrusive btw. Lennart -- Lennart Poettering Red Hat, Inc. lennart [at] poettering [dot] net http://0pointer.net/lennart/ GnuPG 0x1A015CC4