From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751126AbVHQOJL (ORCPT ); Wed, 17 Aug 2005 10:09:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751134AbVHQOJL (ORCPT ); Wed, 17 Aug 2005 10:09:11 -0400 Received: from omx1-ext.sgi.com ([192.48.179.11]:14537 "EHLO omx1.americas.sgi.com") by vger.kernel.org with ESMTP id S1751126AbVHQOJK (ORCPT ); Wed, 17 Aug 2005 10:09:10 -0400 Date: Wed, 17 Aug 2005 07:07:57 -0700 (PDT) From: Christoph Lameter To: Ulrich Windl cc: Roman Zippel , lkml , George Anzinger , frank@tuxrocks.com, Anton Blanchard , benh@kernel.crashing.org, Nishanth Aravamudan Subject: Re: [RFC - 0/9] Generic timekeeping subsystem (v. B5) In-Reply-To: <4302F098.11683.53787EA@rkdvmks1.ngate.uni-regensburg.de> Message-ID: References: <1124151001.8630.87.camel@cog.beaverton.ibm.com> <4302F098.11683.53787EA@rkdvmks1.ngate.uni-regensburg.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Aug 2005, Ulrich Windl wrote: > whatever the implementation is, at some point there must exist an interface go get > and set "normal time", free of any jumps and jitter. That "frontend time" will be > used a a base of correction. Basically that means time should be as monotonic and > jitter free as possible for any measurement interval you like. The interpolator provides such a time as xtime + offset and will self-tune to be as accurate as possible given fluctuations of the timer interrupt. It will even adapt to NTP interval variations.