From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 10 Aug 2001 13:37:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 10 Aug 2001 13:37:24 -0400 Received: from [63.194.239.202] ([63.194.239.202]:15090 "EHLO mmp-linux.matchmail.com") by vger.kernel.org with ESMTP id ; Fri, 10 Aug 2001 13:37:12 -0400 Date: Fri, 10 Aug 2001 10:36:49 -0700 From: Mike Fedyk To: linux-kernel@vger.kernel.org Subject: Re: kapm-idled shows 90+% cpu usage when idle Message-ID: <20010810103649.D28914@mikef-linux.matchmail.com> Mail-Followup-To: linux-kernel@vger.kernel.org In-Reply-To: <200108100036.CAA09153@harpo.it.uu.se> <20010810020152Z269890-28344+3523@vger.kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20010810020152Z269890-28344+3523@vger.kernel.org> User-Agent: Mutt/1.3.20i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > On Thu, 9 Aug 2001 19:33:42 -0400, safemode wrote: > > >Is this a true usage reading or just some quirk that's supposed to happen? > > >I really doubt that this kernel daemon should really be using cpu. It > > > seems to respond with a higher cpu usage when i'm idle. It immediately > > > goes away when something else uses cpu. If you need any more info just > > > ask. I'm > > > On Thursday 09 August 2001 20:36, Mikael Pettersson wrote: > > Do you have CONFIG_APM_CPU_IDLE=y in your .config? If so, disable it. > > > > There was a thread about this problem some months ago. I found > > that on all of my APM-capable machines, including a Dell laptop, > > CONFIG_APM_CPU_IDLE=y had a negative effect. The kernel ended up > > in a tight loop performing tons of APM IDLE BIOS calls, since each > > BIOS call returned immediately without having idled the CPU. > > > > Leaving CONFIG_APM_CPU_IDLE unset lets the kernel use its own > > "HLT when idle" code. On my main development box, idle CPU > > temperature dropped >10 degrees C, and kapm-idled now uses 0% CPU. > > > > /Mikael > On Thu, Aug 09, 2001 at 10:01:55PM -0400, safemode wrote: > I've been told by others that this is exactly what's supposed to happen. It > acts like it's using cpu when it's idle and does it job that way. I see no > difference either way. I'm using a KA7 motherboard and it says it supports > apm and lspci shows what i pasted in the original post. Oh well, it's not > causing the cpu to generate more heat than it would be idle. If you don't see any benefit, I'd disable it just because of the modified results from top...