From dev-return-37480-archive-asf-public=cust-asf.ponee.io@subversion.apache.org Thu Feb 15 20:57:21 2018 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by mx-eu-01.ponee.io (Postfix) with SMTP id 9F19918064A for ; Thu, 15 Feb 2018 20:57:20 +0100 (CET) Received: (qmail 56247 invoked by uid 500); 15 Feb 2018 19:57:14 -0000 Mailing-List: contact dev-help@subversion.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Delivered-To: mailing list dev@subversion.apache.org Received: (qmail 56232 invoked by uid 99); 15 Feb 2018 19:57:14 -0000 Received: from mail-relay.apache.org (HELO mailrelay2-lw-us.apache.org) (207.244.88.137) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 15 Feb 2018 19:57:14 +0000 Received: from [192.168.1.5] (unknown [81.174.159.228]) by mailrelay2-lw-us.apache.org (ASF Mail Server at mailrelay2-lw-us.apache.org) with ESMTPSA id 568D8230; Thu, 15 Feb 2018 19:57:12 +0000 (UTC) Subject: Re: Backward or forward deltas, backend, FSX To: =?UTF-8?B?UMOpdGVy?= , dev@subversion.apache.org References: <808f4972-26b9-5e38-4ced-e71c5bd071c9@prolan-power.hu> From: Julian Foad Message-ID: <624c4af6-c3f0-4444-c51e-eedef6d68ebe@apache.org> Date: Thu, 15 Feb 2018 19:57:10 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <808f4972-26b9-5e38-4ced-e71c5bd071c9@prolan-power.hu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Péter wrote: > [I am not a list member] > > In the proposed FSX backend, > [ https://subversion.apache.org/docs/release-notes/1.9.html#fsx ] > what type of deltas is planned? Deltas against an older - or newer > revision? > [ http://svn.apache.org/repos/asf/subversion/trunk/notes/skip-deltas ] > FSFS-like way, or BDB-like way? > > Please explain it, why was that chosen. Why is optimal. Or, if not quite > decided/fixed, please consider carefully. > > > I know almost nothing (nor want to) about the internals ("fulltext and > txdelta caching" etc.), but: > I would (as everybody :) prefer the variant which uses less space (less > cache, maybe only one - the last revision), and at the same time less > time for extracting revision, with strong weight to the last (just > added) revision, and the last few revisions. > > With say, 100000 revisions, when someone checks out the last revision: > svn starts (would start, with the FSX backend) with the 30 years old, > "fossile" ancient revision? (It would be case with the "FSFS-like way".) > Which has nothing common with the recent revisions? And applies (at > least) 17 deltas (patches)? Of which many deltas are very "heavy" (huge > changings, complete rewritings)?.. I would marvel at that and do not > understand the reasons.. > > > Peter > > > > >