From owner-freebsd-current@FreeBSD.ORG Sat Oct 11 18:30:11 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 231F316A4B3 for ; Sat, 11 Oct 2003 18:30:11 -0700 (PDT) Received: from mail.inka.de (quechua.inka.de [193.197.184.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id D8FC343F3F for ; Sat, 11 Oct 2003 18:30:09 -0700 (PDT) (envelope-from mailnull@mips.inka.de) Received: from kemoauc.mips.inka.de (uucp@) by mail.inka.de with gbsmtp id 1A8V3g-0000Fv-01; Sun, 12 Oct 2003 03:30:08 +0200 Received: from kemoauc.mips.inka.de (localhost [127.0.0.1]) h9C0tSQc023436 for ; Sun, 12 Oct 2003 02:55:28 +0200 (CEST) (envelope-from mailnull@kemoauc.mips.inka.de) Received: (from mailnull@localhost) by kemoauc.mips.inka.de (8.12.10/8.12.10/Submit) id h9C0tSoO023435 for freebsd-current@freebsd.org; Sun, 12 Oct 2003 02:55:28 +0200 (CEST) (envelope-from mailnull) From: naddy@mips.inka.de (Christian Weisgerber) Date: Sun, 12 Oct 2003 00:55:27 +0000 (UTC) Message-ID: Originator: naddy@mips.inka.de (Christian Weisgerber) To: freebsd-current@freebsd.org Subject: idprio safe? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 12 Oct 2003 01:30:11 -0000 Is it safe nowadays to run a process at idle priority? Or is there still the danger of priority inversion / a deadlock? On FreeBSD 4.x you can run a process, such as setiathome, at nice level 19 and it will (almost) only ever get CPU time when no process of normal priority competes with it. FreeBSD 5.x is much "fairer" in this respect, which has the unpleasant result that such a background process will noticeably compete for CPU now. -- Christian "naddy" Weisgerber naddy@mips.inka.de