From mboxrd@z Thu Jan 1 00:00:00 1970 From: Karsten Blees Subject: Re: [PATCH/RFC] read-cache: fix file time comparisons with different precisions Date: Tue, 29 Sep 2015 12:23:37 +0200 Message-ID: <560A66A9.2010606@gmail.com> References: <5605D88A.20104@gmail.com> <560918F8.1080905@gmail.com> <763be6c1331ac57cf7dee3636d82f994@dscho.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Git List To: Johannes Schindelin X-From: git-owner@vger.kernel.org Tue Sep 29 12:23:47 2015 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Zgs4V-0003ja-Jz for gcvg-git-2@plane.gmane.org; Tue, 29 Sep 2015 12:23:44 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934041AbbI2KXl (ORCPT ); Tue, 29 Sep 2015 06:23:41 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:34449 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756227AbbI2KXj (ORCPT ); Tue, 29 Sep 2015 06:23:39 -0400 Received: by wicfx3 with SMTP id fx3so143083751wic.1 for ; Tue, 29 Sep 2015 03:23:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=n/pXi/wAhGY1+OoMpQfd1FT8DC7ChjdSKH+Q8Q8qv9M=; b=vluGyZ8LHT+sbP7MHTrhGklrictqlbzDqz2LWi7OyBysmHPOEXRTfpKHVXR+7hAPFd IfIHfq/TdGtYU/kUc6A/fhzSF1b1z7AymB9LiFSetAbZzyyoULlBFcEWBw7Cacyi6c5f 3vOzLxt/xtST684j9xpzDEcwphODK/TLQLKPfNB5u0ylewjnKZaZF3xppjuFtjGYn5YM OVnY45TYpVLLcyLK3Aej678zudN/qNDmr11ki5+2WnzPBlkREf09NE+W4XnhY/sDrcU1 OC+V4KMgvcDjvQ1S+bPt9J8Ud04gWOUTPB12Phexrr0SR7PuTz/FRKiRlSuXyg6rCA68 lqow== X-Received: by 10.180.230.197 with SMTP id ta5mr23084720wic.26.1443522217800; Tue, 29 Sep 2015 03:23:37 -0700 (PDT) Received: from [10.1.116.51] (ns.dcon.de. [77.244.111.149]) by smtp.googlemail.com with ESMTPSA id lm3sm23079358wjc.39.2015.09.29.03.23.36 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Sep 2015 03:23:36 -0700 (PDT) User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 In-Reply-To: <763be6c1331ac57cf7dee3636d82f994@dscho.org> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Am 28.09.2015 um 14:52 schrieb Johannes Schindelin: > Otherwise there would be that little loop-hole where (nsec % 1000) == 0 *by chance* and we assume the timestamps to be identical even if they are not. Yeah, but in this case the file would be racy, as racy-checks use the same comparison now. IMO change detection is so fundamental that it should Just Work, without having a plethora of config options that we need to explain to end users. If that means that once in a million cases we need an extra content check to revalidate such falsely racy entries, that's fine with me. Cheers, Karsten