Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751658AbXB0Qps (ORCPT ); Tue, 27 Feb 2007 11:45:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751678AbXB0Qps (ORCPT ); Tue, 27 Feb 2007 11:45:48 -0500 Received: from mx1.redhat.com ([66.187.233.31]:50617 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751072AbXB0Qpr (ORCPT ); Tue, 27 Feb 2007 11:45:47 -0500 Date: Tue, 27 Feb 2007 11:44:27 -0500 From: Dave Jones To: Venkatesh Pallipadi Cc: linux-kernel , Andrew Morton , linux-acpi@vger.kernel.org, Adam Belay , Shaohua Li , Len Brown Subject: Re: [PATCH 1/3]cpuidle take2: Core cpuidle infrastructure Message-ID: <20070227164427.GB2223@redhat.com> Mail-Followup-To: Dave Jones , Venkatesh Pallipadi , linux-kernel , Andrew Morton , linux-acpi@vger.kernel.org, Adam Belay , Shaohua Li , Len Brown References: <20070222135257.A26335@unix-os.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070222135257.A26335@unix-os.sc.intel.com> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1404 Lines: 31 On Thu, Feb 22, 2007 at 01:52:57PM -0800, Venkatesh Pallipadi wrote: > Announcing 'cpuidle', a new CPU power management infrastructure to manage > idle CPUs in a clean and efficient manner. > cpuidle separates out the drivers that can provide support for multiple types > of idle states and policy governors that decide on what idle state to use > at run time. > A cpuidle driver can support multiple idle states based on parameters like > varying power consumption, wakeup latency, etc (ACPI C-states for example). > A cpuidle governor can be usage model specific (laptop, server, > laptop on battery etc). > Main advantage of the infrastructure being, it allows independent development > of drivers and governors and allows for better CPU power management. I played with this a little, and got puzzled. My quad core box used exactly the same amount of power whether the 'ladder' governer was loaded & in use or not. In both situations it was exactly the same as a vanilla 2.6.20 I'd have expected it to use more until I loaded up 'ladder' to bring it on par featurewise with 2.6.20. What did I miss? Dave -- http://www.codemonkey.org.uk - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/