From owner-freebsd-questions@FreeBSD.ORG Mon May 25 22:44:30 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 01B76106566C for ; Mon, 25 May 2009 22:44:30 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (wojtek.tensor.gdynia.pl [IPv6:2001:4070:101:2::1]) by mx1.freebsd.org (Postfix) with ESMTP id 0B4BE8FC12 for ; Mon, 25 May 2009 22:44:28 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (localhost [IPv6:::1]) by wojtek.tensor.gdynia.pl (8.14.3/8.14.3) with ESMTP id n4PMi5NB042061; Tue, 26 May 2009 00:44:05 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from localhost (wojtek@localhost) by wojtek.tensor.gdynia.pl (8.14.3/8.14.3/Submit) with ESMTP id n4PMi3uu042058; Tue, 26 May 2009 00:44:03 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Date: Tue, 26 May 2009 00:44:03 +0200 (CEST) From: Wojciech Puchar To: Bruce Cran In-Reply-To: <20090525222810.57e96c4a@gluon.draftnet> Message-ID: References: <200905241315.n4ODFB96007801@mp.cs.niu.edu> <4A1A58FA.60303@boosten.org> <1932D812-03CF-48AF-A306-669C39862EB7@boosten.org> <29229B06-6098-4488-9E9A-A5CFE6F9643B@boosten.org> <20090525222810.57e96c4a@gluon.draftnet> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Mailman-Approved-At: Tue, 26 May 2009 00:27:36 +0000 Cc: Yuri , Scott Bennett , freebsd-questions@freebsd.org, utisoft@gmail.com, Peter Boosten Subject: Re: How can this 'top' command output make sense? Load over 7 and total CPU use ~5% X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 May 2009 22:44:30 -0000 >> performing at 100%... > > While it's not the default behaviour, if you run powerd(8) then > yes, the CPU will run slower when it's less utilized. that's extra,and very useful option. anyway even without that modern processor gets MUCH less power just when being halted by hlt instruction. there is still some power used for clock network within chip, and gate oxide leakage, but almost no other gate switching. just using hlt takes down power usage to 1/3-1/5 of full power. reducing clock with turn it down even more. i'm not sure but turning modern processors on lower speed this way (powerd) change voltage down too a bit which even reduces leakage. anyway powerd didn't work well on my laptop last time i tried, but it was with FreeBSD 6, maybe something changed - i will try this. maybe it will add some 10-20 minutes more battery life. anyway lots of power is used by my UMTS modem, and i can't disconnect it as i usually do need the net while using laptop.