From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Pitre Subject: Re: [PATCH] always start looking up objects in the last used pack first Date: Wed, 30 May 2007 23:24:55 -0400 (EDT) Message-ID: References: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Content-Transfer-Encoding: 7BIT Cc: git@vger.kernel.org To: Junio C Hamano X-From: git-owner@vger.kernel.org Thu May 31 05:25:41 2007 Return-path: Envelope-to: gcvg-git@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1HtbI8-0006ty-RZ for gcvg-git@gmane.org; Thu, 31 May 2007 05:25:37 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758077AbXEaDY7 (ORCPT ); Wed, 30 May 2007 23:24:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756079AbXEaDY7 (ORCPT ); Wed, 30 May 2007 23:24:59 -0400 Received: from relais.videotron.ca ([24.201.245.36]:12029 "EHLO relais.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758077AbXEaDY6 (ORCPT ); Wed, 30 May 2007 23:24:58 -0400 Received: from xanadu.home ([74.56.106.175]) by VL-MO-MR001.ip.videotron.ca (Sun Java System Messaging Server 6.2-2.05 (built Apr 28 2005)) with ESMTP id <0JIV00AV2YTJGO20@VL-MO-MR001.ip.videotron.ca> for git@vger.kernel.org; Wed, 30 May 2007 23:24:56 -0400 (EDT) In-reply-to: X-X-Sender: nico@xanadu.home Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: On Wed, 30 May 2007, Nicolas Pitre wrote: > To test this I split the Linux repository into 66 packs and performed a > "time git-rev-list --objects --all > /dev/null". Best results are as > follows: > > Pack Sort w/o this patch w/ this patch > ------------------------------------------------------------- > recent objects last 26.4s 20.9s > recent objects first 24.9s 18.4s > > This shows that the pack order based on object age has some influence, > but that the last-used-pack heuristic is even more significant in > reducing object lookup. For reference, the same operation on a fully packed into a single pack repository takes 17.1s. So this looks damn good to me. Nicolas