From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 9 Aug 2001 22:02:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 9 Aug 2001 22:02:02 -0400 Received: from mail11.speakeasy.net ([216.254.0.211]:41741 "EHLO mail11.speakeasy.net") by vger.kernel.org with ESMTP id ; Thu, 9 Aug 2001 22:01:45 -0400 Content-Type: text/plain; charset=US-ASCII From: safemode To: Mikael Pettersson , linux-kernel@vger.kernel.org Subject: Re: kapm-idled shows 90+% cpu usage when idle Date: Thu, 9 Aug 2001 22:01:55 -0400 X-Mailer: KMail [version 1.3] In-Reply-To: <200108100036.CAA09153@harpo.it.uu.se> In-Reply-To: <200108100036.CAA09153@harpo.it.uu.se> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: <20010810020152Z269890-28344+3523@vger.kernel.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 09 August 2001 20:36, Mikael Pettersson wrote: > 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 > > 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 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.