From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261711AbVAITZK (ORCPT ); Sun, 9 Jan 2005 14:25:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261710AbVAITZK (ORCPT ); Sun, 9 Jan 2005 14:25:10 -0500 Received: from moutng.kundenserver.de ([212.227.126.171]:62674 "EHLO moutng.kundenserver.de") by vger.kernel.org with ESMTP id S261711AbVAITXl (ORCPT ); Sun, 9 Jan 2005 14:23:41 -0500 Subject: Re: [PATCH] scheduling priorities with rlimit From: utz lehmann To: Arjan van de Ven Cc: LKML , Chris Wright In-Reply-To: <1105297598.4173.52.camel@laptopd505.fenrus.org> References: <1105290936.24812.29.camel@segv.aura.of.mankind> <1105297598.4173.52.camel@laptopd505.fenrus.org> Content-Type: text/plain Date: Sun, 09 Jan 2005 20:23:32 +0100 Message-Id: <1105298613.24812.42.camel@segv.aura.of.mankind> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 (2.0.2-3) Content-Transfer-Encoding: 7bit X-Provags-ID: kundenserver.de abuse@kundenserver.de auth:5a3828f1c4d839cf12e8a3b808f7ed34 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2005-01-09 at 20:06 +0100, Arjan van de Ven wrote: > On Sun, 2005-01-09 at 18:15 +0100, utz lehmann wrote: > > Hi > > > > I really like the idea of controlling the maximum settable scheduling > > priorities via rlimit. See the Realtime LSM thread. I want to give users > > the right to raise the priority of previously niced jobs. > > > > I have modified Chris Wright's patch (against 2.6.10): > > (http://marc.theaimsgroup.com/?l=linux-kernel&m=110513793228776&w=2) > > > > - allow always to increase nice levels (lower priority). > > - set the default for RLIMIT_PRIO to 0. > > - add the other architectures. > > > > With this the default is compatible with the old behavior. > > > > With RLIMIT_PRIO > 0 a user is able to raise the priority up to the > > value. 0-39 for nice levels 19 .. -20, 40-139 for realtime priorities > > (0 .. 99). > > this is a bit of an awkward interface don't you think? > I much rather have the rlimit match the exact nice values we communicate > to userspace elsewhere, both to be consistent and to not expose > scheduler internals to userpsace. Yes it is. But rlimits are unsigned .-( (asm/resource.h says this). I prefer rlimit match nice value too, but how to do this with unsigned. And what do with the RT prio, different rlimit? Btw: I saw this on a solaris command too, 0-39 for nice, 40-139 for RT (dont rememer which). > > Also I like the idea of allowing sysadmins to make certain users/groups > nice levels 5 and higher (think a university machine that makes all > students nice 5 and higher only, while giving staff 0 and higher, and > the sysadmin -5 and higher ;) You can do this already. "priority" item in /etc/security/limits.conf. But they can only lower the priority. This patch is for allowing to raise it.