From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751237AbWGLPck (ORCPT ); Wed, 12 Jul 2006 11:32:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751399AbWGLPck (ORCPT ); Wed, 12 Jul 2006 11:32:40 -0400 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:41623 "EHLO ebiederm.dsl.xmission.com") by vger.kernel.org with ESMTP id S1751237AbWGLPcj (ORCPT ); Wed, 12 Jul 2006 11:32:39 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Andi Kleen Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] sysctl: Allow /proc/sys without sys_sysctl References: <200607121532.05227.ak@suse.de> <200607121652.21920.ak@suse.de> Date: Wed, 12 Jul 2006 09:32:02 -0600 In-Reply-To: <200607121652.21920.ak@suse.de> (Andi Kleen's message of "Wed, 12 Jul 2006 16:52:21 +0200") Message-ID: User-Agent: Gnus/5.110004 (No Gnus v0.4) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andi Kleen writes: >> So it will correctly handle that sysctl being compiled out, and >> the fallback to using /proc. The code seems to have been >> doing that since it was added to glibc in 2000. > > Using /proc is extremly slow for this. How so it is the same code in the kernel. Is open much slower than sys_sysctl? > You added significant cost to each program startup. Not each program only the ones that use pthreads. > I still think it's a good idea to simulate that sysctl and printk > the others. To reduce the noise something like that makes sense. I'm going to see if I can get glibc to use uname which should have the same effect. Eric