From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sam Vilain Subject: Re: Decompression speed: zip vs lzo Date: Fri, 11 Jan 2008 19:29:51 +1300 Message-ID: <47870CDF.4010606@vilain.net> References: <7v4pdmfw27.fsf@gitster.siamese.dyndns.org> <47855765.9090001@vilain.net> <47856E8D.4010006@vilain.net> <4785A6DB.3080007@vilain.net> <20080110091607.GA17944@artemis.madism.org> <478691EB.1080704@vilain.net> <47869C24.3000400@vilain.net> <4786BFCD.1000303@vilain.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Nicolas Pitre , Pierre Habouzit , Git Mailing List , Johannes Schindelin , Marco Costalba , Junio C Hamano To: Linus Torvalds X-From: git-owner@vger.kernel.org Fri Jan 11 07:30:40 2008 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1JDDPa-0003Nh-5Z for gcvg-git-2@gmane.org; Fri, 11 Jan 2008 07:30:38 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751759AbYAKGaK (ORCPT ); Fri, 11 Jan 2008 01:30:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751729AbYAKGaK (ORCPT ); Fri, 11 Jan 2008 01:30:10 -0500 Received: from watts.utsl.gen.nz ([202.78.240.73]:56116 "EHLO mail.utsl.gen.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751617AbYAKGaI (ORCPT ); Fri, 11 Jan 2008 01:30:08 -0500 Received: by mail.utsl.gen.nz (Postfix, from userid 65534) id 72CDD21D192; Fri, 11 Jan 2008 19:29:58 +1300 (NZDT) Received: from [192.168.2.22] (leibniz.catalyst.net.nz [202.78.240.7]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.utsl.gen.nz (Postfix) with ESMTP id CC00F21D18C; Fri, 11 Jan 2008 19:29:52 +1300 (NZDT) User-Agent: Icedove 1.5.0.12 (X11/20070606) In-Reply-To: X-Enigmail-Version: 0.94.2.0 X-Spam-Checker-Version: SpamAssassin 3.0.3 (2005-04-27) on mail.musashi.utsl.gen.nz X-Spam-Level: X-Spam-Status: No, score=-2.8 required=5.0 tests=ALL_TRUSTED autolearn=failed version=3.0.3 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Linus Torvalds wrote: > > On Fri, 11 Jan 2008, Sam Vilain wrote: >> Without compression of deltas: >> >> wilber:~/src/perl-preview$ du -sk .git/objects/pack/ >> 86781 .git/objects/pack/ >> >> With compression of deltas: >> >> wilber:~/src/perl-preview$ du -sk .git/objects/pack/ >> 72907 .git/objects/pack/ > > Ok, so non-compressed deltas are 20% bigger. > > That may well be a perfectly acceptable trade-off if the end result is > then a lot faster. Has somebody done performance numbers? I may have > missed them.. The best test is probably something like "git blame" on a > file that takes an appreciable amount of time. The difference seems only barely measurable; wilber:~/src/perl-preview$ time git annotate sv.c >/dev/null real 0m8.130s user 0m6.712s sys 0m1.412s wilber:~/src/perl-preview-loose$ time git annotate sv.c >/dev/null real 0m7.930s user 0m6.480s sys 0m1.408s (each one is last of three runs - dual-core x86_64 @ 2.1GHz w/512KB cache) sv.c has about 1500 revisions, though the oldest line is I also tried annotate and log on the YACC generated parser which only has about 165 revisions, with similar results - a very minor difference or no difference. Sam