From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754190Ab0ENFnr (ORCPT ); Fri, 14 May 2010 01:43:47 -0400 Received: from e23smtp08.au.ibm.com ([202.81.31.141]:52372 "EHLO e23smtp08.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753750Ab0ENFnp (ORCPT ); Fri, 14 May 2010 01:43:45 -0400 Date: Fri, 14 May 2010 11:13:36 +0530 From: Balbir Singh To: Lennart Poettering Cc: Peter Zijlstra , Dhaval Giani , James Kosin , linux-kernel@vger.kernel.org, menage@google.com, jsafrane@redhat.com, tglx@linutronix.de Subject: Re: [PATCH/RFC] Have sane default values for cpusets Message-ID: <20100514054336.GX3296@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com 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> <20100514000252.GB30093@tango.0pointer.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20100514000252.GB30093@tango.0pointer.de> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Lennart Poettering [2010-05-14 02:02:52]: > 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. > I think the config options are the domains of the distributors and if the code is there and works, most distros will enable it. As long as they have a feature that uses that option or a need for it. I am not sure why CONFIG_CGROUP=y is so bad, Peter, could you elaborate? -- Three Cheers, Balbir