From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: Decompression speed: zip vs lzo Date: Wed, 09 Jan 2008 14:55:44 -0800 Message-ID: <7v4pdmfw27.fsf@gitster.siamese.dyndns.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Git Mailing List" To: "Marco Costalba" X-From: git-owner@vger.kernel.org Wed Jan 09 23:56:32 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 1JCjqP-0003qx-L9 for gcvg-git-2@gmane.org; Wed, 09 Jan 2008 23:56:22 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751555AbYAIWzx (ORCPT ); Wed, 9 Jan 2008 17:55:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752942AbYAIWzx (ORCPT ); Wed, 9 Jan 2008 17:55:53 -0500 Received: from a-sasl-quonix.sasl.smtp.pobox.com ([208.72.237.25]:43140 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751026AbYAIWzw (ORCPT ); Wed, 9 Jan 2008 17:55:52 -0500 Received: from a-sasl-quonix (localhost [127.0.0.1]) by a-sasl-quonix.pobox.com (Postfix) with ESMTP id 663854E21; Wed, 9 Jan 2008 17:55:49 -0500 (EST) Received: from pobox.com (ip68-225-240-77.oc.oc.cox.net [68.225.240.77]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by a-sasl-quonix.pobox.com (Postfix) with ESMTP id DF4734E20; Wed, 9 Jan 2008 17:55:46 -0500 (EST) In-Reply-To: (Marco Costalba's message of "Wed, 9 Jan 2008 23:01:36 +0100") User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: "Marco Costalba" writes: > P.S: Compression size is better for zip but a more realistic test > would be to try with a delta packaged repo instead of a simple tar of > source files. Because delta packaged is already compressed in his way > perhaps difference in final file sizes is smaller. Note that the space nor time performance of compressing and uncompressing a single huge blob is not as interesting in the context of git as compressing/uncompressing millions of small pieces whose total size is comparable to the specimen of "huge single blob" experiment. Obviously loose object files are compressed individually, and packfile contents are also individually and independently compressed. Set-up cost for individual invocation of compression and uncompression on smaller data matters a lot more than an experiment on compressing and uncompressiong a single huge blob (this applies to both time and space).