From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753182AbXDIRbE (ORCPT ); Mon, 9 Apr 2007 13:31:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753191AbXDIRbE (ORCPT ); Mon, 9 Apr 2007 13:31:04 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:47636 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753182AbXDIRbB (ORCPT ); Mon, 9 Apr 2007 13:31:01 -0400 Date: Mon, 9 Apr 2007 12:30:53 -0500 From: Robin Holt To: "Eric W. Biederman" Cc: Roland McGrath , Oleg Nesterov , Andrew Morton , Davide Libenzi , Ingo Molnar , Linus Torvalds , Robin Holt , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [RFC, PATCH 1/3] introduce SYS_CLONE_MASK Message-ID: <20070409173053.GD22997@lnx-holt.americas.sgi.com> References: <20070409020600.6338BD82F4@pipsqueak.sf.frob.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org OK. I just got the OK from management. The system we were booting was for research only. We had NR_CPUS=num_online_cpus()=4096 which were non-hyperthreaded. With no attached I/O and the tweak I originally posted plus one change Jack has already gotten accepted, the machine booted in approx 12 minutes. Thanks, Robin On Mon, Apr 09, 2007 at 10:20:27AM -0600, Eric W. Biederman wrote: > Roland McGrath writes: > > > I concur with Eric's assessment. Adding new magic bits to the generic > > clone path seems like a poor way to cope with kernel threads. I think > > it's better if kernel thread setup gets less like normal user process > > setup. I also agree with Eric that PPID of 0 is a very natural way for > > kernel threads to be displayed. We need to know more about the nature > > of the compatibility issue in procps to judge whether there is good > > reason to avoid changing it. > > I just investigated the procps issue. Using init_task as the parent > nothing sticks out as being wrong in /proc. > > Further when I modified pstree to accept 0 as it's starting pid (from > which all else would be rooted). All of the kernel threads showed up. > > So if anything I it is a feature that kernel threads don't show up > by default in pstree (when PPID == 0). It isn't a subtle kernel bug. > > Eric