Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 1 Aug 2002 12:25:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 1 Aug 2002 12:25:47 -0400 Received: from neon-gw-l3.transmeta.com ([63.209.4.196]:19465 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Thu, 1 Aug 2002 12:25:47 -0400 Date: Thu, 1 Aug 2002 09:30:04 -0700 (PDT) From: Linus Torvalds To: Alan Cox cc: Chris Friesen , Benjamin LaHaise , Pavel Machek , Andrea Arcangeli , , Subject: Re: [rfc] aio-core for 2.5.29 (Re: async-io API registration for 2.5.29) In-Reply-To: <1028223041.14865.80.camel@irongate.swansea.linux.org.uk> Message-ID: 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 Content-Length: 1113 Lines: 28 On 1 Aug 2002, Alan Cox wrote: > > For a lot of applications like multimedia you actually want a counting > of time not any relation to real time except that you can tell how many > ticks elapse a second. Absolutely. I think "jiffies64" is fine (as long as is it converted to some "standard" time-measure like microseconds or nanoseconds so that people don't have to care about internal kernel state) per se. The only thing that I think makes it less than wonderful is really the fact that we cannot give an accurate measure for it. We can _say_ that what we count in microseconds, but it might turn out that instead of the perfect 1000000 ticks a second ther would really be 983671 ticks. A 2% error may not be a big problem for most people, of course. But it might be a huge problem for others. Those people would have to do their own re-calibration.. Linus - 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/