From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH v3 0/3] automatically skip away from broken commits Date: Wed, 10 Jun 2009 15:43:47 -0700 Message-ID: <4A303723.4060805@zytor.com> References: <20090606043853.4031.78284.chriscool@tuxfamily.org> <4A2CAA56.1030707@zytor.com> <7vws7n6vcf.fsf@alter.siamese.dyndns.org> <4A2D337C.70203@zytor.com> <7vzlcixwue.fsf@alter.siamese.dyndns.org> <4A2E7EEC.2050807@zytor.com> <7viqj5kutl.fsf@alter.siamese.dyndns.org> <7vtz2nlrfs.fsf@alter.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Christian Couder , Christian Couder , git@vger.kernel.org, Sam Vilain , Ingo Molnar To: Junio C Hamano X-From: git-owner@vger.kernel.org Thu Jun 11 00:50:42 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1MEWcz-0004eD-UE for gcvg-git-2@gmane.org; Thu, 11 Jun 2009 00:50:42 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756437AbZFJWu3 (ORCPT ); Wed, 10 Jun 2009 18:50:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756766AbZFJWu2 (ORCPT ); Wed, 10 Jun 2009 18:50:28 -0400 Received: from terminus.zytor.com ([198.137.202.10]:33493 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756437AbZFJWu0 (ORCPT ); Wed, 10 Jun 2009 18:50:26 -0400 Received: from anacreon.sc.intel.com (hpa@localhost [127.0.0.1]) (authenticated bits=0) by terminus.zytor.com (8.14.3/8.14.1) with ESMTP id n5AMhl7a004850 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 10 Jun 2009 15:43:48 -0700 User-Agent: Thunderbird 2.0.0.21 (X11/20090320) In-Reply-To: <7vtz2nlrfs.fsf@alter.siamese.dyndns.org> X-Virus-Scanned: ClamAV 0.94.2/9451/Wed Jun 10 11:05:54 2009 on terminus.zytor.com X-Virus-Status: Clean Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Junio C Hamano wrote: > Christian Couder writes: > >> On Tue, Jun 9, 2009 at 10:37 PM, Junio C Hamano wrote: >>> Christian Couder writes: >>> >>>> My opinion is that we should not penalize all the people working on >>>> "quite clean" projects and also people working on "not clean" projects >>>> who are able to recover, on the pretence that there are other people >>>> on these "not clean" projects who are not. >> ... >> When I wrote "clean", I just mean with not too many untestable commits. > > Ok, then the "opinion" in the above paragraph was simply stating the > obvious: we should have a good "bisect skip". I obviously agree with that > ;-). > > In other words, you were not arguing against my observation that your > algorithm would not be much better than randomly picking the next commit > when the best one is untestable, unless the history is linear. I guess > that was what I was confused with. I thought you were saying that we > should give preferential treatment to people with linear history. > >> Ok. I started working on optionaly using a PRNG but I am not sure that >> you will want to add another one. > > It may still make sense to replace, not add to, that "fixed alternating > distance in goodness space" with a randomized one, for the reasons HPA > stated, especially for avoiding to give a false impression that the magic > constants are picked for some reason. > That being said, Christian's observation that a biased selection would be better than a linear random pick is a good one. -hpa