From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: Re: [PATCH 3/3] revision: insert unsorted, then sort in prepare_revision_walk() Date: Mon, 2 Apr 2012 16:51:12 -0400 Message-ID: <20120402205112.GA28824@sigill.intra.peff.net> References: <201203291818.49933.mfick@codeaurora.org> <201204021024.49706.mfick@codeaurora.org> <201204021049.04901.mfick@codeaurora.org> <20120402203728.GB26503@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Martin Fick , =?utf-8?B?UmVuw6k=?= Scharfe , Shawn Pearce , Junio C Hamano , git@vger.kernel.org To: Shawn Pearce X-From: git-owner@vger.kernel.org Mon Apr 02 22:51:22 2012 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1SEoDe-0004S2-Vi for gcvg-git-2@plane.gmane.org; Mon, 02 Apr 2012 22:51:19 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752514Ab2DBUvO (ORCPT ); Mon, 2 Apr 2012 16:51:14 -0400 Received: from 99-108-226-0.lightspeed.iplsin.sbcglobal.net ([99.108.226.0]:43541 "EHLO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751861Ab2DBUvO (ORCPT ); Mon, 2 Apr 2012 16:51:14 -0400 Received: (qmail 21318 invoked by uid 107); 2 Apr 2012 20:51:15 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.84) with ESMTPA; Mon, 02 Apr 2012 16:51:15 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Mon, 02 Apr 2012 16:51:12 -0400 Content-Disposition: inline In-Reply-To: <20120402203728.GB26503@sigill.intra.peff.net> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Mon, Apr 02, 2012 at 04:37:28PM -0400, Jeff King wrote: > Has anyone looked seriously at a new index format that stores the > redundant information in a more easily accessible way? It would increase > our disk usage, but for something like linux-2.6, only by 10MB per > 32-bit word. On most of my systems I would gladly spare some extra RAM > for the disk cache if it meant I could avoid inflating a bunch of > objects. Actually, that is an over-statement of the size. That would be a per-object piece of metadata. A per-commit piece like timestamp would be only 1M per 32-bit word in linux-2.6 (about 1/4 million commits). Or put another way, we could store timestamps and 20-byte parent sha1s in about 11M. -Peff