From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268092AbUHFCpQ (ORCPT ); Thu, 5 Aug 2004 22:45:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268097AbUHFCow (ORCPT ); Thu, 5 Aug 2004 22:44:52 -0400 Received: from pirx.hexapodia.org ([65.103.12.242]:19828 "EHLO pirx.hexapodia.org") by vger.kernel.org with ESMTP id S268063AbUHFCmX (ORCPT ); Thu, 5 Aug 2004 22:42:23 -0400 Date: Thu, 5 Aug 2004 21:42:21 -0500 From: Andy Isaacson To: William Lee Irwin III , Marcelo Tosatti , "Mr. Berkley Shands" , linux-kernel@vger.kernel.org Subject: Re: Severe I/O performance regression 2.6.6 to 2.6.7 or 2.6.8-rc3 Message-ID: <20040806024221.GA19333@hexapodia.org> References: <41126811.7020607@dssimail.com> <20040805172531.GC17188@holomorphy.com> <4112917A.3080003@cse.wustl.edu> <20040805204615.GJ17188@holomorphy.com> <20040805223319.GA18155@logos.cnet> <20040806020930.GA23072@hexapodia.org> <20040806022734.GN17188@holomorphy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040806022734.GN17188@holomorphy.com> User-Agent: Mutt/1.4.1i X-PGP-Fingerprint: 48 01 21 E2 D4 E4 68 D1 B8 DF 39 B2 AF A3 16 B9 X-PGP-Key-URL: http://web.hexapodia.org/~adi/pgp.txt X-Domestic-Surveillance: money launder bomb tax evasion Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 05, 2004 at 07:27:34PM -0700, William Lee Irwin III wrote: > At some point in the past, I wrote: > >>> Some form of changelogging to enumerate what the contents of the > >>> 2.6.6-bk6 -> 2.6.6-bk7 delta are and to reconstruct intermediate points > >>> between 2.6.6-bk6 and 2.6.6-bk7 is needed. > > On Thu, Aug 05, 2004 at 09:09:30PM -0500, Andy Isaacson wrote: > > So if the -bkX creation script doesn't already, it should "bk changes > > -r+ -d:KEY: > key-bk$X" when it creates the tarball. Then anyone can > > "bk clone -r`cat key-bk7` linux-2.5 linux-2.6-bk7" and duplicate the > > -bk7 state of the tree, and then "bk changes -L ../linux-2.6-bk6" to > > find the list of changesets differing. > > Once we get there, there must be some way to construct intermediate > points between those two faithful at the very least to the snapshot > ordering if not true chronological ordering. Well, the state of the "central tree" is represented by a cset key at each point. So the answer to your question is a list of keys. But the keys in question aren't "special" in any bk sense; they're just some keys. You can keep track of keys outside of BK if you want, to keep a history of "state of this tree at time X", but BK can't keep track of that info. Anyways, maybe an example is in order. % bk prs -hnd:KEY: -rv2.5.4-pre6..v2.5.4 ChangeSet torvalds@home.transmeta.com|ChangeSet|20020211032403|18448 torvalds@home.transmeta.com|ChangeSet|20020211014924|18455 torvalds@home.transmeta.com|ChangeSet|20020211013331|26396 paulus@quango.(none)|ChangeSet|20020211005601|64956 davej@suse.de|ChangeSet|20020211004458|26395 rml@tech9.net|ChangeSet|20020210234603|34727 kai@vaio.(none)|ChangeSet|20020210234057|58664 gkernel.adm@hostme.bitkeeper.com|ChangeSet|20020210215119|34443 rml@tech9.net|ChangeSet|20020210205932|34726 Those are the changesets that are present in 2.5.4 that aren't present in 2.5.4-pre6 (note how I used tag..tag in the -r option.) Similarly, you can do -r'rml@tech9.net|ChangeSet|20020210205932|34726..davej@suse.de|ChangeSet|20020211004458|26395' (that is, "key1..key2") to find the keys implied by key2 and not implied by key1. (Read "bk help set" for even more sophisticated options.) Pick the interesting csets and do a binary search... (Or better, write a script to do it!) -andy