From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH v4 2/2] cgroups: add a pids subsystem Date: Mon, 9 Mar 2015 15:51:17 -0400 Message-ID: <20150309195117.GW13283@htj.duckdns.org> References: <1424660891-12719-1-git-send-email-cyphar@cyphar.com> <1425606357-6337-1-git-send-email-cyphar@cyphar.com> <1425606357-6337-3-git-send-email-cyphar@cyphar.com> <20150309033405.GE13283@htj.duckdns.org> <54FDED43.4050908@gmail.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=zMvdNFNXDPXgavcQacD5PObgF4B+/6hlhjYkNyzAgJ0=; b=O+MVGQVzeERmj/kffpVUZ3Y33F2Ea8H08HI/Nu4VMzp+QGyjqKYEpAah+cmwPrN/sF h09CRdQfjYkZJOIyY1/HSGqmPC+lDPIZafo5m4eFC62tbHw2VgMtReZzCgIIu1/HNKiD aO08T+tBFtTDJ902Wa+W05f8Jg0flAGaLNnwSrLA1L0eNL8QaKLIHo6GsGVwH7ItRsK6 sOKT8KbxdYKtvWu7V6kCPdcSkWJEwNPmdYQCyreT6c6zP2IFRPlUV1ySyGbWHyXqJ84e THvfmytpR9jeVu13WFNAXnBuR1NWqGUOY6BYSs2HppM1kfVqAbUMhDWRBASc2wMyl4Y8 c5mw== Content-Disposition: inline In-Reply-To: <54FDED43.4050908-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Austin S Hemmelgarn Cc: Aleksa Sarai , lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, richard-/L3Ra7n9ekc@public.gmane.org, fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Hello, Austin. On Mon, Mar 09, 2015 at 02:58:11PM -0400, Austin S Hemmelgarn wrote: > On 2015-03-08 23:34, Tejun Heo wrote: > > > >Does pids limit make sense in the root cgroup? > > > I would say it kind of does, although I would just expect it to track > /proc/sys/kernel/pid_max (either as a read-only value, or as an alternative > way to set it). I don't think that's a good idea. It doesn't add anything while putting pids controller in conflict with how other controllers handle the root cgroup. Furthermore, I don't think it's generally a good idea to add things because it may help convenience in some cases, which is exactly the case here. Why add non-orthogonal component when the only reason is "yeah, it may be a bit more convenient in some imaginary cases"? We'd be restricting the design space we can move inside for no good reason. Thanks. -- tejun