From owner-freebsd-current@FreeBSD.ORG Thu Oct 20 12:10:34 2005 Return-Path: X-Original-To: current@freebsd.org 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 81DA416A41F for ; Thu, 20 Oct 2005 12:10:34 +0000 (GMT) (envelope-from Alexander@Leidinger.net) Received: from www.ebusiness-leidinger.de (jojo.ms-net.de [84.16.236.246]) by mx1.FreeBSD.org (Postfix) with ESMTP id 96E7243D69 for ; Thu, 20 Oct 2005 12:10:32 +0000 (GMT) (envelope-from Alexander@Leidinger.net) Received: from Andro-Beta.Leidinger.net (p54A5D4B6.dip.t-dialin.net [84.165.212.182]) (authenticated bits=0) by www.ebusiness-leidinger.de (8.13.1/8.13.1) with ESMTP id j9KBq336083206; Thu, 20 Oct 2005 13:52:07 +0200 (CEST) (envelope-from Alexander@Leidinger.net) Received: from localhost (localhost [127.0.0.1]) by Andro-Beta.Leidinger.net (8.13.3/8.13.3) with ESMTP id j9KCANXP023620; Thu, 20 Oct 2005 14:10:23 +0200 (CEST) (envelope-from Alexander@Leidinger.net) Received: from pslux.cec.eu.int (pslux.cec.eu.int [158.169.9.14]) by netchild.homeip.net (Horde MIME library) with HTTP; Thu, 20 Oct 2005 14:10:23 +0200 Message-ID: <20051020141023.0ejwdv4dss48wko0@netchild.homeip.net> X-Priority: 3 (Normal) Date: Thu, 20 Oct 2005 14:10:23 +0200 From: Alexander Leidinger To: Nate Lawson References: <200510172310.j9HNAVPL013057@repoman.freebsd.org> <20051018094402.A29138@grasshopper.cs.duke.edu> <435501B9.4070401@samsco.org> <43553162.5040802@root.org> In-Reply-To: <43553162.5040802@root.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format="flowed" Content-Disposition: inline Content-Transfer-Encoding: 7bit User-Agent: Internet Messaging Program (IMP) H3 (4.0.3) / FreeBSD-4.11 X-Virus-Scanned: by amavisd-new Cc: current@freebsd.org Subject: 1kHz noise from C3 sleep (was: Re: cvs commit: src/sys/amd64/amd64 cpu_switch.S machdep.c) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Thu, 20 Oct 2005 12:10:34 -0000 Nate Lawson wrote: [Moving to -current] >> I wonder if moving to HZ=1000 on amd64 and i386 was really all that good >> of an idea. Having preemption in the kernel means that ithreads can run >> right away instead of having to wait for a tick, and various fixes to >> 4BSD in the past year have eliminated bugs that would make the CPU wait >> for up to a tick to schedule a thread. So all we're getting now is a >> 10x increase in scheduler overhead, including reading the timecounters. > > I use hz=100 on my systems due to the 1 khz noise from C3 sleep. > Windows has the same problem. My laptop makes noises when being (more or less) idle (I think I enabled C3...). Does this mean I should try to change HZ? If yes: Windows doesn't make such a noise, does this mean it doesn't use C3 on this system (your comment suggests that Windows does use a HZ=1000 like behavior)? Bye, Alexander. -- http://www.Leidinger.net Alexander @ Leidinger.net: PGP ID = B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137 The last person who quit or was fired will be held responsible for everything that goes wrong -- until the next person quits or is fired.