Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261509AbVEYRi3 (ORCPT ); Wed, 25 May 2005 13:38:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261512AbVEYRi2 (ORCPT ); Wed, 25 May 2005 13:38:28 -0400 Received: from zcars04e.nortelnetworks.com ([47.129.242.56]:11410 "EHLO zcars04e.ca.nortel.com") by vger.kernel.org with ESMTP id S261509AbVEYRiP (ORCPT ); Wed, 25 May 2005 13:38:15 -0400 Message-ID: <4294B7ED.2030307@nortel.com> Date: Wed, 25 May 2005 11:37:49 -0600 X-Sybari-Space: 00000000 00000000 00000000 00000000 From: Chris Friesen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040115 X-Accept-Language: en-us, en MIME-Version: 1.0 To: george@mvista.com CC: bhavesh@avaya.com, linux-kernel@vger.kernel.org Subject: Re: 2.6.11 timeval_to_jiffies() wrong for ms resolution timers References: <1116975555.2050.10.camel@cof110earth.dr.avaya.com> <4294B42D.2020008@mvista.com> In-Reply-To: <4294B42D.2020008@mvista.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 756 Lines: 20 George Anzinger wrote: > Bhavesh P. Davda wrote: >> setitimer for 20ms was firing at 21ms > If we do NOT account for this PIT issue, the result is a time drift that > is outside of what ntp can handle... Still, it is non-intuitive that a multi-GHz machine can't wake you up more accurately than 1ms. What about telling it to wake up a jiffy earlier, then checking whether the scheduling lag was enough to cause it to have waited the full specified time. If not, put it to sleep for another jiffy. Chris - 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/