From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Pearce Subject: Re: 1.3.0 creating bigger packs than 1.2.3 Date: Thu, 20 Apr 2006 21:01:46 -0400 Message-ID: <20060421010146.GA819@spearce.org> References: <20060420164351.GB31738@spearce.org> <20060420175554.GH31738@spearce.org> <7v8xq0yteb.fsf@assigned-by-dhcp.cox.net> <7vfyk8vscl.fsf@assigned-by-dhcp.cox.net> <20060420220240.GB32748@spearce.org> <7vy7xzvpsg.fsf@assigned-by-dhcp.cox.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Nicolas Pitre , git@vger.kernel.org X-From: git-owner@vger.kernel.org Fri Apr 21 03:02:04 2006 Return-path: Envelope-to: gcvg-git@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by ciao.gmane.org with esmtp (Exim 4.43) id 1FWk21-0008OW-Bc for gcvg-git@gmane.org; Fri, 21 Apr 2006 03:01:57 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932195AbWDUBBy (ORCPT ); Thu, 20 Apr 2006 21:01:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932197AbWDUBBy (ORCPT ); Thu, 20 Apr 2006 21:01:54 -0400 Received: from corvette.plexpod.net ([64.38.20.226]:44688 "EHLO corvette.plexpod.net") by vger.kernel.org with ESMTP id S932195AbWDUBBy (ORCPT ); Thu, 20 Apr 2006 21:01:54 -0400 Received: from cpe-72-226-60-173.nycap.res.rr.com ([72.226.60.173] helo=asimov.home.spearce.org) by corvette.plexpod.net with esmtpa (Exim 4.52) id 1FWk1i-0002mJ-3s; Thu, 20 Apr 2006 21:01:38 -0400 Received: by asimov.home.spearce.org (Postfix, from userid 1000) id 92A4A20FBB4; Thu, 20 Apr 2006 21:01:46 -0400 (EDT) To: Junio C Hamano Content-Disposition: inline In-Reply-To: <7vy7xzvpsg.fsf@assigned-by-dhcp.cox.net> User-Agent: Mutt/1.5.11 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - corvette.plexpod.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - spearce.org X-Source: X-Source-Args: X-Source-Dir: Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: Junio C Hamano wrote: [snip] > I suspect the test patch makes pack-objects a lot more > expensive. Which patch are you talking about the previous patch or the one in the message I'm now replying to? > The code before the test patch said "if the size is very small > or size difference is too great, do not consider this, and do > not consider any more objects in the delta window, because we > know they are either even smaller of the same path, they have > different names, or they are of different type". The test patch > you tried was a quick and dirty hack that said "under the > too-small condition, skip this one, but keep trying the rest of > the delta window". > > Here is a cleaned up patch. What it does is "under the > too-small condition, see if the object has the same basename, > and if so keep going, but otherwise skip the rest as before". [snip] The patch below does not help very much: Total 46391, written 46391 (delta 6686), reused 37979 (delta 0) 129M pack-7f766f5af5547554bacb28c0294bd562589dc5e7.pack > diff --git a/pack-objects.c b/pack-objects.c > index 09f4f2c..2173709 100644 > --- a/pack-objects.c > +++ b/pack-objects.c > @@ -1036,8 +1036,6 @@ static int try_delta(struct unpacked *cu > oldsize = old_entry->size; > sizediff = oldsize > size ? oldsize - size : size - oldsize; > > - if (size < 50) > - return -1; > if (old_entry->depth >= max_depth) > return 0; > > @@ -1048,20 +1046,27 @@ static int try_delta(struct unpacked *cu > * more space-efficient (deletes don't have to say _what_ they > * delete). > */ > - max_size = size / 2 - 20; > - if (cur_entry->delta) > - max_size = cur_entry->delta_size-1; > - if (sizediff >= max_size) > - return -1; > - delta_buf = diff_delta(old->data, oldsize, > - cur->data, size, &delta_size, max_size); > - if (!delta_buf) > + if (50 <= size) { > + max_size = size / 2 - 20; > + if (cur_entry->delta) > + max_size = cur_entry->delta_size-1; > + if (sizediff < max_size) { > + delta_buf = diff_delta(old->data, oldsize, > + cur->data, size, > + &delta_size, max_size); > + if (!delta_buf) > + return 0; > + cur_entry->delta = old_entry; > + cur_entry->delta_size = delta_size; > + cur_entry->depth = old_entry->depth + 1; > + free(delta_buf); > + return 0; > + } > + } > + /* Keep going as long as the basename matches */ > + if (((cur_entry->hash ^ old_entry->hash) >>DIRBITS) == 0) > return 0; > - cur_entry->delta = old_entry; > - cur_entry->delta_size = delta_size; > - cur_entry->depth = old_entry->depth + 1; > - free(delta_buf); > - return 0; > + return -1; > } > > static void progress_interval(int signum) > -- Shawn.