From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759271AbZEGUIG (ORCPT ); Thu, 7 May 2009 16:08:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754083AbZEGUHv (ORCPT ); Thu, 7 May 2009 16:07:51 -0400 Received: from smtp3.ultrahosting.com ([74.213.175.254]:33092 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755225AbZEGUHv (ORCPT ); Thu, 7 May 2009 16:07:51 -0400 Date: Thu, 7 May 2009 15:56:46 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@qirst.com To: Alan Cox cc: "Paul E. McKenney" , Peter Zijlstra , Alok Kataria , "H. Peter Anvin" , Ingo Molnar , Thomas Gleixner , the arch/x86 maintainers , LKML Subject: Re: [PATCH] x86: Reduce the default HZ value In-Reply-To: <20090507205357.1be739e1@lxorguk.ukuu.org.uk> Message-ID: References: <1241462661.412.8.camel@alok-dev1> <4A00ADDE.9000908@zytor.com> <1241560625.8665.17.camel@alok-dev1> <1241716053.6311.1514.camel@laptop> <1241716422.6311.1524.camel@laptop> <1241716718.6311.1531.camel@laptop> <20090507173608.GC6693@linux.vnet.ibm.com> <1241717904.6311.1558.camel@laptop> <20090507180112.GE6693@linux.vnet.ibm.com> <20090507205357.1be739e1@lxorguk.ukuu.org.uk> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 7 May 2009, Alan Cox wrote: > Even then its pointlessly jumping up and down and changing stuff rather > than fixing the real problem - which is jiffies. Reducing the number of application interruptions by a factor of 10 is not pointless. The lower HZ becomes the more useless it will become for the users of jiffies because they will have to create timers and use time intervals if the HZ intervals become too large.