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=-6.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B487FC433E0 for ; Fri, 31 Jul 2020 15:27:49 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8341922B42 for ; Fri, 31 Jul 2020 15:27:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Z5cWm7ZW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8341922B42 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57084 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k1Wwm-0004My-Jm for qemu-devel@archiver.kernel.org; Fri, 31 Jul 2020 11:27:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37772) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k1Wvn-0003V2-7O for qemu-devel@nongnu.org; Fri, 31 Jul 2020 11:26:47 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:20682 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1k1Wvl-0006Zy-K6 for qemu-devel@nongnu.org; Fri, 31 Jul 2020 11:26:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1596209205; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yJh7LwqnSJ4fWnx9paVcnQmM8xau82cYPCN3q5zToNE=; b=Z5cWm7ZWPpFEdX/hRTTTWA3VmU3Nv5dYzbVowzWPSRjfEuI5VJDlyhHXhZZ5fXzGBIoLp+ 5dUPhJnMz4qenc40DimMH0NmFJD7TM/bex2UXhb/e68yQJVE5LzXLet6ERDbdNH5eOQWQp 6rGlMkhxGqlZ14zNIGxKrfEhciv17Qg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-437-VvddpSatN36IQBYxRGRCcg-1; Fri, 31 Jul 2020 11:26:41 -0400 X-MC-Unique: VvddpSatN36IQBYxRGRCcg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D6AB8107ACCA; Fri, 31 Jul 2020 15:26:39 +0000 (UTC) Received: from ibm-p8-OVS-01-fsp.mgmt.pnr.lab.eng.rdu2.redhat.com (ovpn-113-142.rdu2.redhat.com [10.10.113.142]) by smtp.corp.redhat.com (Postfix) with ESMTP id 35CBA57; Fri, 31 Jul 2020 15:26:29 +0000 (UTC) Subject: Re: [PATCH] schemas: Add vim modeline To: =?UTF-8?Q?Daniel_P=2e_Berrang=c3=a9?= , Markus Armbruster References: <20200729185024.121766-1-abologna@redhat.com> <87ime52wxd.fsf@dusky.pond.sub.org> <20200730093732.GB3477223@redhat.com> <87k0ylz0ep.fsf@dusky.pond.sub.org> <20200730132446.GL3477223@redhat.com> <875za33ku1.fsf@dusky.pond.sub.org> <20200731150738.GB3660103@redhat.com> From: John Snow Message-ID: <03bb7822-20a0-2945-6c86-1d5f1b2a01d9@redhat.com> Date: Fri, 31 Jul 2020 11:26:28 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200731150738.GB3660103@redhat.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=207.211.31.120; envelope-from=jsnow@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/31 04:39:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , qemu-block@nongnu.org, "Michael S. Tsirkin" , Jason Wang , Juan Quintela , qemu-devel@nongnu.org, Yuval Shaia , Gerd Hoffmann , Andrea Bolognani , =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= , Paolo Bonzini , Michael Roth , "Dr. David Alan Gilbert" , Stefan Berger Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 7/31/20 11:07 AM, Daniel P. Berrangé wrote: > On Fri, Jul 31, 2020 at 02:55:34PM +0200, Markus Armbruster wrote: >> Daniel P. Berrangé writes: > >>>> Some of the criticism there doesn't matter for our use case. >>> >>> Yeah, what matters is whether it can do the job we need in a way that is >>> better than what we have today, and whether there are any further options >>> to consider that might be viable alternatives. >> >> Would it improve things enough to be worth the switching pain? > > The short answer is that I don't think that question matters. We should > do the conversion regardless, as our JSON-but-not file format has no > compelling reason to exist as a thing when there's a variety of standard > file formats that could do the job. I'd explicitly ignore the sunk costs > and minor amount of work to convert to a new format. > This is not a language we spend a lot of time editing, too. Is it really such a big cost to re-learn a tiny language like this? That concern seems overplayed, in my view. > The long answer is that as a general philosophy I'm in favour of agressively > eliminating anything that is custom to a project and isn't offering an > compelling benefit over a functionally equivalent, commonly used / standard > solution. > I agree as violently as I know how. The purpose of this is not for us, it's for the ecosystem. I saw the critique that we still use JSON-ish for the runtime QMP protocol, and moving the QAPI IDL to a standard wouldn't remove all instances of a custom format from our tree. This is actually a great argument for doing the other thing: moving QMP onto a standard protocol. The point is not to complicate matters for QEMU developers, but to simplify matters for developers from other projects who are integrating QEMU. > Any time a project re-invents the wheel, that is one more piece of custom > knowledge a contributor has to learn. Each one may seem insignificant on > its own, but cummulatively they result in death by a 1000 cuts. This makes > a project increasingly less attractive to contribute to over the long term. > > Measuring the long term benefit of the change is generally quite difficult, > because while you can see what impact a change will have today on current > code, it is hard to usefully evaluate future benefits as you're trying to > imagine the impact on things that don't even exist. > > Overall my POV is not to think too hard about measuring improvements, and > discard any concern about sunk costs. Instead have a general presumption > in favour of eliminating any examples of wheel re-invention in a project. > Even if regular contributors don't want to spend time on such work, this > kind of thing is pretty amenable to new contributors looking for tasks to > start their involvement. > > The QAPI JSON-but-not file format is a case where I think we should just > adopt a standard file format no matter what. A conversion will have some > short term work, but this is really simple data to deal with and the code > involved is nicely self contained. Again I'm not saying QAPI maintainers > must do it, just put the idea out there as a piece of work that would > be welcomed if someone is interested in working ont. > I have a lot of code trying to pylint and mypy-ify the QAPI parser, and a prototype YAML parser. The work that remains to be done is hooking up my new YAML parser into the code generator. Assuming I am able to continue working on this, an RFC could be soon. > Another example would be elimination of anything in QEMU code that is > duplicating functionality in GLib, even if there zero functional > difference between the two impls. > > Another example would be adopting a standard code style and using a > tool like clang-format to enforce this for entire of existing code > base and future contributions and throwing away our checkpatch.pl > which nearly everyone is scared of touching as it is Perl code. > > Regards, > Daniel >