From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261506AbVGWDeX (ORCPT ); Fri, 22 Jul 2005 23:34:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262315AbVGWDeX (ORCPT ); Fri, 22 Jul 2005 23:34:23 -0400 Received: from viper.oldcity.dca.net ([216.158.38.4]:46493 "HELO viper.oldcity.dca.net") by vger.kernel.org with SMTP id S261506AbVGWDeW (ORCPT ); Fri, 22 Jul 2005 23:34:22 -0400 Subject: Re: Giving developers clue how many testers verified certain kernel version From: Lee Revell To: Linus Torvalds Cc: Alejandro Bonilla , Blaisorblade , LKML , Andrian Bunk , "H. Peter Anvin" In-Reply-To: References: <200507230244.11338.blaisorblade@yahoo.it> <42E1986B.8070202@linuxwireless.org> <1122088160.6510.7.camel@mindpipe> <42E1A832.7010604@linuxwireless.org> <1122088863.6510.19.camel@mindpipe> Content-Type: text/plain Date: Fri, 22 Jul 2005 23:34:18 -0400 Message-Id: <1122089660.6510.29.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.2.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2005-07-22 at 20:31 -0700, Linus Torvalds wrote: > > On Fri, 22 Jul 2005, Lee Revell wrote: > > > > Con's interactivity benchmark looks quite promising for finding > > scheduler related interactivity regressions. > > I doubt that _any_ of the regressions that are user-visible are > scheduler-related. They all tend to be disk IO issues (bad scheduling or > just plain bad drivers), and then sometimes just VM misbehaviour. > > People are looking at all these RT patches, when the thing is that most > nobody will ever be able to tell the difference between 10us and 1ms > latencies unless it causes a skip in audio. I agree re: the RT patches, but what makes Con's benchmark useful is that it also tests interactivity (measuring in msecs vs. usecs) with everything running SCHED_NORMAL, which is a much better approximation of a desktop load. And the numbers do go well up into the range where people would notice, tens and hundreds of ms. Lee