From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH 4/3] t3700: avoid racy git situation Date: Thu, 08 Nov 2007 12:42:40 -0800 Message-ID: <7vbqa431vj.fsf@gitster.siamese.dyndns.org> References: <47331E65.9010209@viscovery.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Johannes Sixt , git@vger.kernel.org, krh@redhat.com To: Johannes Schindelin X-From: git-owner@vger.kernel.org Thu Nov 08 21:43:21 2007 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 1IqEDT-0004po-2a for gcvg-git-2@gmane.org; Thu, 08 Nov 2007 21:43:07 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760783AbXKHUmv (ORCPT ); Thu, 8 Nov 2007 15:42:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754656AbXKHUmv (ORCPT ); Thu, 8 Nov 2007 15:42:51 -0500 Received: from sceptre.pobox.com ([207.106.133.20]:44606 "EHLO sceptre.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754177AbXKHUmu (ORCPT ); Thu, 8 Nov 2007 15:42:50 -0500 Received: from sceptre (localhost.localdomain [127.0.0.1]) by sceptre.pobox.com (Postfix) with ESMTP id 88B202FC; Thu, 8 Nov 2007 15:43:09 -0500 (EST) Received: from pobox.com (ip68-225-240-77.oc.oc.cox.net [68.225.240.77]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by sceptre.sasl.smtp.pobox.com (Postfix) with ESMTP id C7AD893923; Thu, 8 Nov 2007 15:43:04 -0500 (EST) In-Reply-To: (Johannes Schindelin's message of "Thu, 8 Nov 2007 15:16:17 +0000 (GMT)") User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: Johannes Schindelin writes: > The problem is that the index has the same timestamp as the file "foo". > > Therefore, git cannot tell if "foo" is up-to-date in the index, since it > could have been modified (and indeed is) just a fraction of a second later > than the index was last updated. > > And since diff-index, as called from the test script, does not generate a > diff, but really only determines if the index information suggests that > the files are up-to-date, there is not really much you can do. > > This is our good old friend, the racy git problem. That sounds very wrong. What happened to the ce_smudge_racily_clean_entry() call that is done from write_index()? > NOTE: other scms do not have this problem, mostly because they are too > slow to trigger it. I recall racy-hg mentioned on their development list twice, a few months apart, and CVS has the "delay the return from a commit to the next full second" or something to work around problems in the timestamp recorded in CVS/Entries.