From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.1 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD shortcircuit=no autolearn=no autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 51C762023D for ; Wed, 1 Mar 2017 21:09:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751816AbdCAVJM (ORCPT ); Wed, 1 Mar 2017 16:09:12 -0500 Received: from mail-yw0-f176.google.com ([209.85.161.176]:35403 "EHLO mail-yw0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751154AbdCAVJK (ORCPT ); Wed, 1 Mar 2017 16:09:10 -0500 Received: by mail-yw0-f176.google.com with SMTP id d1so43011866ywd.2 for ; Wed, 01 Mar 2017 13:08:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=ViELpjSvZ6wX2jz9Pt5/5iRgH7XbfvWE1Lw1gy2uFs0=; b=j3rJHb9wyZgahRtBtCMTOOZEiTEFIHf0LdcqmB79ZiAm/Gz+9KTzFRKAsH+dfy78B6 p17xKk86uYf0/XYHgnDPJ0K0sS19oH3Yfy1+T4qiCWL/Azd2QVknCZL1gI1NdGDmjasJ EEZT/wX7F8TT0l8WaYN1Bz7jAM4G2vuYYJMdgLVv+igcQGO2wl36+zUZzTh1SXkmjYMM E+Zdv5GBr6lmEcl3WNZaB+bDvPbSLfbN8QAo72oaEl1++W6bO8/4HSx7Tr31lmx69iEL VnhzBqAeYmMIusDLssnGbc9mXxwd4kS5UK0r7kaPFohzmBQF/n5NOolj1g7HTZT0o85L xoMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=ViELpjSvZ6wX2jz9Pt5/5iRgH7XbfvWE1Lw1gy2uFs0=; b=rJcSc29imITD+G6ZOJK4FIulK6cm/+rq6OE0OmSS+kJnEPBNPrw3QlOGnY154H1sEN gLMb0YcW/mcr636Db16M+LOmvb7N0G7XxDq6ZRH4r6hPWuvc63/fom130O80Ahm0OSfr zOEjMd3DtQ9+JEhoucYFB8TZ38qBDZkc0uSeeltht7Qwttz+RPcJxoGmcl2IEe/UtPsu VB82D3EbvwYS9y4drI2e7TF+t5a85MN1Qw9xVPb5yVz6jyDT3ea2r8cgnhKiN0bfWUHd DjC+IXGmtwD9jH1Hugu5NCCy7liDDgaYHINeUaw5owajNQPBfAUupeXHoiwkLvDCKA8K e+1w== X-Gm-Message-State: AMke39mwdpZFZMkR8+9pT+nTdU0p7nwD2uXgaKpWYSlcLHotC3d/K4MYbKxty17f62xHKBh+84Cqm8JhOnZ/Vw== X-Received: by 10.37.73.194 with SMTP id w185mr3828893yba.5.1488402504543; Wed, 01 Mar 2017 13:08:24 -0800 (PST) MIME-Version: 1.0 Received: by 10.129.67.40 with HTTP; Wed, 1 Mar 2017 13:08:04 -0800 (PST) In-Reply-To: References: <4d2a1852-8c84-2869-78ad-3c863f6dcaf7@gmail.com> From: Martin Langhoff Date: Wed, 1 Mar 2017 16:08:04 -0500 Message-ID: Subject: Re: Delta compression not so effective To: Linus Torvalds Cc: Marius Storm-Olsen , Git Mailing List Content-Type: text/plain; charset=UTF-8 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Mar 1, 2017 at 1:30 PM, Linus Torvalds wrote: > For example, the sorting code thinks that objects with the same name > across the history are good sources of deltas. Marius has indicated he is working with jar files. IME jar and war files, which are zipfiles containing Java bytecode, range from not delta-ing in a useful fashion, to pretty good deltas. Depending on the build process (hi Maven!) there can be enough variance in the build metadata to throw all the compression machinery off. On a simple Maven-driven project I have at hand, two .war files compiled from the same codebase compressed really well in git. I've also seen projects where storage space is ~101% of the "uncompressed" size. my 2c, m -- martin.langhoff@gmail.com - ask interesting questions ~ http://linkedin.com/in/martinlanghoff - don't be distracted ~ http://github.com/martin-langhoff by shiny stuff