From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 6D7911F87F for ; Tue, 20 Nov 2018 15:07:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726139AbeKUBgg (ORCPT ); Tue, 20 Nov 2018 20:36:36 -0500 Received: from mail-qk1-f193.google.com ([209.85.222.193]:34506 "EHLO mail-qk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725851AbeKUBgf (ORCPT ); Tue, 20 Nov 2018 20:36:35 -0500 Received: by mail-qk1-f193.google.com with SMTP id a132so3059026qkg.1 for ; Tue, 20 Nov 2018 07:07:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=9rufB7sVHZ9Io+04YkVwfBccuXA5ZMPf5njXIs2kDCs=; b=fp/Kdc6qWMsuxstC/86AM/l8JXR9jdWRp44YBCdJ2EK6cXKWOQQgx7pEiXnTOAc1TQ Os+oMe6jApVpomcIkiMfS67/drF2Du2F1UplM8kT3A4xAdvCYN7R812LKOC90ZWBkAk8 OKckO226q2W4YcGbYVUG8CKTZGIEPmh2fB14vmBZJ5LSnLmC3lucVV3uH2uX336LBV48 HMVad0slYOVptEOBVgt01SG3/CBbffkPHx41ti2TyJ6YI6YJm05TvMdZzgWXcATtJouO qMcbZ2xhDeDlipDsdwGor2m+RnCsPwIIxoO78z0VFKJA3FHG6z6wXpUfsIwAuyH/x03Y eDwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=9rufB7sVHZ9Io+04YkVwfBccuXA5ZMPf5njXIs2kDCs=; b=V0Nfij9ntOoW6rbHE5sIhmPGX5h3wdYDWEGVHtwKmQU1qd5hYWoUUWTGBAjOfx0TRi a6NhriZvnsaPJdZzrNlVpOMFiVf/3Z9n3v/uczp2NJ1OG5U5UnWcaMne4/4hG1FppcZ4 9KSSufhp+3EctvgsS80yuRaZAsef3e4EquqSFHCjii/viXKguSmk5f3nOuodbAa8rvHv AFv1tQWlaVyg4QfhXOYDrmEwl5gUVPAVDvcVHizg1YfgA/K9XlK3qg5F/1hablHU6c2+ mqqNT4rifJBR8kD4gjhhVKk5HxV1d6qhPTv6P4VkePdcCOgYzVXfsj8U7DsOwVEjZNo9 JxJw== X-Gm-Message-State: AA+aEWY91Ik5nI0ZNSnajb9SzRwdhl0wNAvluEWb7GrSEO19tCI9TGwX zeeMW3Cu6H5aHRyzJZ9WeiM= X-Google-Smtp-Source: AFSGD/WOeY8ETsrSwwb/EWI2GzpqLPqNNvGTdhUboi0H331Vib1mBQh5/eRSSBEPYVPZjuiIBqABag== X-Received: by 2002:a37:d994:: with SMTP id q20mr2069757qkl.116.1542726419727; Tue, 20 Nov 2018 07:06:59 -0800 (PST) Received: from ?IPv6:2001:4898:6808:13e:9842:9c91:9414:a691? ([2001:4898:8010:0:8178:9c91:9414:a691]) by smtp.gmail.com with ESMTPSA id r24sm29403292qtr.2.2018.11.20.07.06.58 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 20 Nov 2018 07:06:58 -0800 (PST) Subject: Re: [PATCH 0/3] delta-island fixes To: Jeff King , git@vger.kernel.org Cc: Christian Couder , Derrick Stolee References: <20181120094451.GA21725@sigill.intra.peff.net> From: Derrick Stolee Message-ID: <778f1fcb-8988-de42-8264-d4394ede8540@gmail.com> Date: Tue, 20 Nov 2018 10:06:57 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:64.0) Gecko/20100101 Thunderbird/64.0 MIME-Version: 1.0 In-Reply-To: <20181120094451.GA21725@sigill.intra.peff.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On 11/20/2018 4:44 AM, Jeff King wrote: > In cases like this I think it's often a good idea to have a perf test. > Those are expensive anyway, and we'd have the double benefit of > exercising the code and showing off the performance improvement. But the > delta-island code only makes sense on a very specialized repo: one where > you have multiple related but diverging histories. You could simulate > that by picking two branches in a repository, but the effect is going to > be miniscule. The changes in this series look correct. Too bad it is difficult to test. Perhaps we should add a performance test for the --delta-islands check that would trigger the failure (and maybe a clone afterwards). There are lots of freely available forks of git.git that present interesting fork structure. Here are three that would suffice to make this interesting:     https://github.com/git/git     https://github.com/git-for-windows/git     https://github.com/microsoft/git Of course, running it on a specific repo is up to the person running the perf suite. Thanks, -Stolee