From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B944C433DF for ; Thu, 28 May 2020 02:46:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E8862084C for ; Thu, 28 May 2020 02:46:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="GA/4cf3y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726793AbgE1CqR (ORCPT ); Wed, 27 May 2020 22:46:17 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:43458 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725896AbgE1CqR (ORCPT ); Wed, 27 May 2020 22:46:17 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04S2SOFY022351; Thu, 28 May 2020 02:46:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=G39A/4UyERydEP85xt6VjuVAFue3xHhfhYVjhjED3lg=; b=GA/4cf3yl4tmXCe1XBbE7tomCG2m1IdfyrfNyEGgiVyI8IuQlC/DxxHTx1xelAeGAA5y J8MbY+7GcKjJgwm8OzMwYjHtS2B0qoQvF+mRDsOcMM8LGiX+evIQhBkNXd0H6tzA2nu7 dtREFTVdJ4VCJ4dnkvcMvIdh/Fk+nd/MNvt988Pp0SsLO1rObT2JR1+zVxjfi7Rp+CH7 iNkHj68Sk4cpYaJmbxN6AlTB5YQPqyMQYWvzrq3x1sg4bE6FxUybGpdxcvoN8TSyLEUl PxkI2gysJ5RmG75wA760yYJcVZRlW8XbQgQJZCnoVNoU4ZG2oC8UA0npB1TE2mTGWabv Ig== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 318xbk2kjx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 28 May 2020 02:46:15 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04S2T5Q3128426; Thu, 28 May 2020 02:44:14 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 317ddrx10t-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 28 May 2020 02:44:14 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 04S2iEmX008248; Thu, 28 May 2020 02:44:14 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 27 May 2020 19:44:14 -0700 Date: Wed, 27 May 2020 19:44:10 -0700 From: "Darrick J. Wong" To: Dave Chinner Cc: xfs Subject: Re: [XFS SUMMIT] Ugh, Rebasing Sucks! Message-ID: <20200528024410.GM252930@magnolia> References: <20200527184858.GM8230@magnolia> <20200528000351.GA2040@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200528000351.GA2040@dread.disaster.area> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9634 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 bulkscore=0 mlxscore=0 phishscore=0 adultscore=0 suspectscore=1 spamscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005280009 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9634 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 spamscore=0 mlxscore=0 lowpriorityscore=0 priorityscore=1501 phishscore=0 cotscore=-2147483648 suspectscore=1 bulkscore=0 clxscore=1015 impostorscore=0 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005280009 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Thu, May 28, 2020 at 10:03:51AM +1000, Dave Chinner wrote: > On Wed, May 27, 2020 at 11:48:58AM -0700, Darrick J. Wong wrote: > > Hi everyone, > > > > Many of you have complained (both publicly and privately) about the > > heavy cost of rebasing your development trees, particularly when you're > > getting close to sending a series out for review. I get it, there have > > been a lot of large refactoring patchsets coming in the past few kernel > > cycles, and this has caused a lot of treewide churn. I don't mind > > cleanups of things that have been weird and wonky about XFS for years, > > but, frankly, rebasing is soul-grinding. > > > > To that end, I propose reducing the frequency of (my own) for-next > > pushes to reduce how often people feel compelled to rebase when they're > > trying to get a series ready for review. > > > > Specifically, I would like to make an informal for-next push schedule as > > follows: > > > > 1 Between -rc1 and -rc4, I'll collect critical bug fixes for the > > merge window that just closed. These should be small changes, so > > I'll put them out incrementally with the goal of landing everything > > in -rc4, and they shouldn't cause major disruptions for anyone else > > working on a big patchset. This is more or less what I've been doing > > up till now -- if it's been on the list for > 24h and someone's > > reviewed it, I'll put it in for-next for wider testing. > > > > 2 A day or two after -rc4 drops. This push is targeted for the next > > merge window. Coming three weeks after -rc1, I hope this will give > > everyone enough time for a round of rebase, review, and debugging of > > large changesets after -rc1. IOWs, the majority of patchsets should > > be ready to go in before we get halfway to the next merge window. > > > > 3 Another push a day or two after -rc6 drops. This will hopefully give > > everyone a second chance to land patchsets that were nearly ready but > > didn't quite make it for -rc4; or other cleanups that would have > > interfered with the first round. Once this is out, we're more or > > less finished with the big patchsets. > > This seems like a reasonable compromise - knowing when updates are > expected goes a long way to being able to plan development and > schedule dev tree updates to avoid repeated rebasing. > > > 4 Perhaps another big push a day or two after -rc8 drops? I'm not keen > > on doing this. It's not often that the kernel goes beyond -rc6 and I > > find it really stressful when the -rc's drag on but people keep > > sending large new patchsets. Talk about stumbling around in the > > dark... > > IMO it's too late at -rc8 to be including big new changes for the > merge window. Bug fixes are fine, but not cleanups or features at > this point because there's too little test and soak time to catch > brown paper bag bugs before it's in the mainline tree and in much > more widespread use. Fair enough. I didn't really like this #4 anyway. Withdrawn. :) > Same goes for merging new stuff during the merge window - last time > around we had updates right up to the merge window, then an update > during the merge window for a second pull request. There just wasn't > any time when the tree wasn't actively moving forward. Urk, sorry about that... I was hoping to land a fix for $largeclient but then the crazy just kept coming. Never gonna do /that/ again. :/ > From my perspective, an update from for-next after the -rc6 update > gets me all the stuff that will be in the next release. That's the > major rebase for my work, and everything pulled in from for-next > starts getting test coverage a couple of weeks out from the merge > window. Once the merge window closes, another local update to the > -rc1 kernel (which should be a no-op for all XFS work) then gets > test coverage for the next release. -rc1 to -rc4 is when > review/rework for whatever I want merged in -rc4/-rc6 would get > posted to the list.... My workflow is rather different -- I rebase my dev tree off the latest rc every week, and when a series is ready I port it to a branch off of for-next. Occasionally I'll port a refactoring from for-next into my dev tree to keep the code bases similar. Both trees get run through fstests and $whatnot whenever they change, which mean that most mornings I'm looking at nightlies. > This means there's a single rebase event a cycle at -rc6, and the > rest of the time the tree is pretty stable and the base tree I'm > testing is almost always the tree that we need to focus dev testing > on. That is, just before the merge window everyone should be testing > for-next on a -rc6/-rc7 base, and once -rc1 is out, everyone should > be testing that kernel through to ~-rc4 at which point it has > largely stabilised and the cycle starts again.... > > > 5 Obviously, I wouldn't hold back on critical bug fixes to things that > > are broken in for-next, since the goal is to promote testing, not > > hinder it. > > *nod* > > > Hopefully this will cut down on the "arrrgh I was almost ready to send > > this but then for-next jumped and nggghghghg" feelings. :/ > > > > Thoughts? Flames? > > Perhaps: > > - each patch set that is posted should start with "this is aimed at > a 5.x.y-rc4/-rc6 merge" or "still work in progress" so that > everyone has some expectation of when changes are likely to land. This would probably help with peoples' ability to distinguish djwong patchbombs for submission vs. making backups on NYE. ;) > or: > > - aim to land features and complex bug fixes in -rc4 and cleanups in > -rc6, that way we naturally minimise the rebase work for the > features/bug fixes that are being landed. This may mean that -rc4 > is a small merge if there are no features/bug fixes that meet the > -rc4 merge criteria... I like that idea. --D > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com