From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, T_DKIM_INVALID shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 3731D208EB for ; Mon, 6 Aug 2018 15:48:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732974AbeHFR6G (ORCPT ); Mon, 6 Aug 2018 13:58:06 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:45900 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728626AbeHFR6G (ORCPT ); Mon, 6 Aug 2018 13:58:06 -0400 Received: by mail-wr1-f67.google.com with SMTP id f12-v6so12807554wrv.12 for ; Mon, 06 Aug 2018 08:48:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version:content-transfer-encoding; bh=y65Fj2VFa6gn9QXmD60aLeeD5SgCOAGN+BUhSTJZPKI=; b=CGaDOEDVsYZGsIP7sjxwBLYaN7rFTvaGIOI1pjuz36CA+wgqE0GaybdUt2QGYomy6T ji5pnJxBXkOFGijL5uTecaV2kl4i3Vel9Gec+LF+dM6I+eds5Xj10QZJh4ZLSVAYsCeJ schctPgOB0uDlx2vBulIKUVrjxcq4jtx51e1E4JEL79C/zZl9HrPhhzx9PLfV291h/62 ajKAxzM5dBxWwl0ki2RwSMAnInhB3uOQC9YzcSnlAFpkVsRBQGGgs48+6+r+AIucjWtG ZwZt+lxaEOAY9SYNAFDvlDPaiJdL+4+S6W06mvituYgxC6SFivs8pTk8DiLqdfxq95QU uxfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:references:date :in-reply-to:message-id:user-agent:mime-version :content-transfer-encoding; bh=y65Fj2VFa6gn9QXmD60aLeeD5SgCOAGN+BUhSTJZPKI=; b=i2YFSsgysWSfuWT2tynv7BomZEt7UIjh2D9jpJQbnAMuUDAHYpDhNnyO8yFFOyilAz pIBp+3E6jnoIdXcd+YlCXLepZoWydBORsVYKqNcloYL2U3deuUpx2Df+6IMhiZY0r66U Ar7asGauI+5mqYoiScrADe9+8Zk2iU+GLE42CzrrgKr6+I0J+EYZM8HpJGdsCCCe+qTv WTu/uCmXF/tEh39IWkEcH6mDm37LMS9K29PgkW4GN9ZcWdZ4pdPMRbLSM5C1zJ9O2kOj VGnZ10+4qh9r1NLtQdGMNjXRLAZO6LHB+BK3M00PQBwu1Cei688iLZih4MCXq9bdMCXH +XRw== X-Gm-Message-State: AOUpUlHPyEyMWKm5cuCkPNqcFvi4T/OTacsIYgOETNzPNpUdHmFpkPTu P0WjSVWOa3/YMF83y88iP9E= X-Google-Smtp-Source: AAOMgpczEexGFpTj3UXyJKTCO2+f3ox9UG265F6hByHkVZnoNJJHQ5FZzmONNR2SByxedb0UiXBcRA== X-Received: by 2002:adf:8362:: with SMTP id 89-v6mr10382935wrd.147.1533570502975; Mon, 06 Aug 2018 08:48:22 -0700 (PDT) Received: from localhost (168.50.187.35.bc.googleusercontent.com. [35.187.50.168]) by smtp.gmail.com with ESMTPSA id j131-v6sm8085743wmb.25.2018.08.06.08.48.21 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 06 Aug 2018 08:48:22 -0700 (PDT) From: Junio C Hamano To: =?utf-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= Duy Cc: Ben.Peart@microsoft.com, git@vger.kernel.org, peartben@gmail.com, peff@peff.net Subject: Re: [PATCH v3 0/4] Speed up unpack_trees() References: <20180729103306.16403-1-pclouds@gmail.com> <20180804053723.4695-1-pclouds@gmail.com> Date: Mon, 06 Aug 2018 08:48:21 -0700 In-Reply-To: <20180804053723.4695-1-pclouds@gmail.com> (=?utf-8?B?Ik5ndXk=?= =?utf-8?B?4buFbiBUaMOhaSBOZ+G7jWM=?= Duy"'s message of "Sat, 4 Aug 2018 07:37:19 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Nguyễn Thái Ngọc Duy writes: > This is a minor update to address Ben's comments and add his > measurements in the commit message of 2/4 for the record. Yay. > I've also checked about the lookahead thing in unpack_trees() to see > if we accidentally break something there, which is my biggest worry. > See [1] and [2] for context, but I believe since we can't have D/F > conflicts, the situation where lookahead is needed will not occur. So > we should be safe. Isn't this about branch switching, where the currently checked out branch may have a regular file 't' and checking out another branch that has directory 't' in it (or vice versa, possibly with the index having either a regular file 't' or requiring 't' to be a diretory by having a blob 't/1' in it)? The log messge of [1] talks about walking three trees together with the index, but even if we limit us to two-tree walk, I do not think that the picture fundamentally changes. So I am not sure how we can confidently say "we can't have D/F". I'd need to block a solid time to take a look at the patches. > [1] da165f470e (unpack-trees.c: prepare for looking ahead in the index - 2010-01-07) > [2] 730f72840c (unpack-trees.c: look ahead in the index - 2009-09-20) Thanks.